rmoyao
Standard Member
A few days ago I decided to convert all the light bulbs in my MG ZS EV 2021 to LED lights for a couple of reasons.
Being an EV whatever you can save in power contributes to the range of the battery. Yes I know that the watt consumption of the lights in the car is minimal against to the total consumption of the HV electric motor and can be ignored but, every watt counts. The headlights are 120 watts (60 w each) over a period of 4 hours they consume almost half of a KW and that is not taking in account the other lights like fog lights (30 w) rear lights (30 w) and others
The second reason, and probably the main reason, to change the lights has to do with the heat they produce and this applicable to ICE vehicles as well. Most of the bases and housings for the lights are made of plastics and even when they are calculated to withstand the high temperature produced by the bulbs with the time they can degrade and cause color variations on the refractive lenses and hardening of the base material. We all have seen the yellowish shade that the cabin lights gets on old cars due to the high temperature of the light bulb. The lower the temperature the longer the life of the plastic. Just touch the exterior of any housing after it has been on for a while and you will feel that they get hot.
The third reason has to do with the cabling on the wire harnesses. The cabling on modern cars is calculated to handle exactly the amperes that the application requires. No less no more just to comply with the security standard. With the time the insulation on the cable degrades. This happens to any cable automotive or not, so the less current you pass thru the cable the longer the life expectancy.
All these reasons can be considered superfluous, because all those effects will take years to takeover but as a general rule I want to avoid them in the future for me of for the next owner of this car.
Anyway. I wanted to share my experience so if you are considering to change some of the bulbs in your car you can take in account several points. So lets start with some comments about every bulb in the car.
Headlamps
Type HB3LL
Base P20d 90°
Consumption 60w each
Also known as 9005 or only HB3 (if you read the manual you will find the the designation of “LL” has to do with the life expectancy of the halogen lamp but not with the shape of the lamp
Replace with HB3 LEDs
There has been a lot of discussions on the forum about changing the headlamps so I will not comment that much. Also there are several YouTube videos on the matter. Besides that I have not received mine since they are on the mail. Just to mention that I decided to go for the Auxbeam F16-plus. I will post more about these lamps once I change them in my car
Please take in account that you need to consider the form factor of the replacement since not all the lights will fit the housing. Also not all the replacements are legal on all countries so you need to consult your dealer to see if you can do the change
Front direction indicators
Type PY21W
Base BAU15S
Consumption 21w each
As known as BAU15S or 7507
Replace with BAU15S LED amber
They are located in the same housing as the main headlamps at the front. Just turn a quarter of turn the base and pull. Take in account that the base BAU15S is very similar to BA15S. The difference will be that the BAU15S has a deviation of 30 degrees on the position on the side pins on the base (the two little pins on each side of the cylinder base) the BA15S are straight with the center of the base cylinder.
So far as I can see on all the bulbs there is no CANBUS control. CANBUS is used for the lights on some cars to report if a bulb is burn and needs to be replaced. It seems that this is not the case for the MG ZS EV. Please correct me if I am wrong
But if you change the turn signal bulbs you will get want some people refers to hyper flashing. That is basically a more rapid flashing of the turn signals. That effect is usually caused because the internal resistance of the LED light is different to the regular incandescent bulbs.
Usually this error is corrected by using load resistors in parallel to the LED lights so they can compensate the resistance on the flash relay. If you use that method the lights will work but in general it defeats the idea of using LED light since you will not be consuming less power just dissipating it on the load resistors, and also you have to modify the cabling and drill holes on your car.
The second method, and less intrusive, is to change the stock flash relay for a solid state relay so it will not be affected by the resistance on the LEDs. They are usually trade as LED ready relays.
That being said, I change all 4 direction indicators (front and back) and I get the hyper flashing. Since I do not want to consume watts on heat on load resistors I started looking for the flash relay to see if it can be replaced, but I was not able to find it. Actually the clicking sound comes from the driver side speaker on the car. It seems that the clicking sound if just a fake audio indication for the driver.
So does anybody knows where is the relay (if any) that controls those lights? Has anybody done the change successfully?. If so any help will be greatly appreciated.
Rear side lights
Type W5W
Base W2.1×9.5d
Consumption 5w each (20 w total)
As known as T10 or 168
Replace with T10 LED white
There are 2 bulbs on the housing located on the tail gate on each side. Obliviously the idea will be to replace them with the same type of LED so you do not get variations on the intensity. I highly recommend to use LEDs that have all around chips and not only on the front since this light is mean to spread so it looks like a continuous light. If you get the ones with only a lens on the front you will get spots of light.
To remove the tail gate housing you do not need to remove the side cover on the housing. Actually I will recommend not to remove it since is held by plastic clips and there is a high risk to break them. To remove the housing open the tail gate, on each side there is a plastic cover on the interior face. You can remove those covers introducing a flat head screw driver on the slot on the cover. I recommend that you use a plastic tool to remove covers. They are a few bucks (or few quids should I say) for the set on Amazon or Ebay otherwise wrap some electrician tape around the head of a flat head screw driver so you avoid any scratch on the plastic finish.
You will get access to the back of the housing and you will see 3 small nuts. Remove them and wiggle the housing, the plastic side cover will not interfere when you pull out the housing. You will find two small bases at each side where you will replace the bulbs
Reverse lights
Type W16W
Base W2.1×9.5d
Consumption 15w each
As known as T15 or 921
Replace with T15 LED white
They are located also on the tail gate housing. Follow the procedure described before to remove the housing.
The W5W (T10) and the W16W (T15) have the same base the difference is that the actual bulb is bigger. So you can replace those lights with T10 lights but the need to be high intensity. The size of T15 LED lights is very similar to the T10s the only difference is that the T15s will have almost double the quantity of LED chips, hence double or triple the light.
I recommend that you use the highest intensity light that you can get as the reverse light reflector is very small. Also they should be all around LEDs so you use the reflector in the housing.
Rear fog lights
Type P21W
Base BA15s
Consumption 21w each
Also known as BA15S or 1156
Replace with BA15S LED white
We have to thank our friends at SAIC for the acrobatics on this one. I don’t see any way to remove the housing other than removing the whole rear bumper. I guess the designer at this point was tired of trying clever ways to give easy access to the user to change the bulbs. Please let me know if you find a way
So in order to change those bulbs you have to lay in your back near to the position of the housing, look inside the rear bumper and you will see the red housing. You will see in the middle of the housing a gray base. You have to introduce your arm (there is a round cut out in the bumper) so you can reach the base and turn it a quarter and pull the base to change the bulb.
BTW in my car they were really stuck because the rubber o-ring to prevent water to get into the housing. I recommend that you apply a little silicon grease around the o-ring so is not that hard to put it back in place.
Thankfully these ones are BA15S base so it does not matter how you place the light it will fit. These lights have to be all around LEDs chips since they are on vertical position
Stop Lights
Type W21/5W
Base W3×16q
Consumption 21+5w each
As know as T20 dual or 7443
Replace with T20 dual LED white.
Please note that if you ask for T20s they will usually will not have two levels of light. You have to make sure the LED that you purchase has two level lights, one high when you press to stop pedal and another low that stays on.
They are located on the rear chassis housing. To access the hex screws that hold the housing on the main chassis you need to remove a cover that is located among the weather rubber seal of the tail gate and the housing. The cover is hold by plastic clips that attach to the housing you just need to pull them. Be very careful when you put them back because they are not very good quality to say the least, and you can break one of the clips.
After you remove the covers you will see the hex screws. You remove them and the wiggle the whole housing to pull it out. There is no other screws or nuts, there is just plastic fasteners and plastic pins that keep the housing in position. The bulb is located on the center of the housing and is bigger than the one on the side.
License plate lights
Type W5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 or 168
Replace with T10 LED white
They are located at each side of the rear camera. Just insert a flat head screw driver on the slot on the transparent housing on the side near to the camera and pull one side. Please note that in order to put it back you have to insert the side with the two hooks first.
Try to replace with LED that will provide as much even distribution of light as possible otherwise you will get spots of light on your license plate
Rear direction indicators
Type WY16W
Base W2.1×9.5d
Consumption 15w each
As known as T15 or 921NA
Replace with T15 LED amber
Located at the rear chassis housing. Follow the procedure described before and the light will be the smaller base on the housing. They will present the same issue that I described on the front direction indicators.
Interior lamp
Type W5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 or 168
Replace with T10 LED white
Insert a small flat head screw driver on the side of the white cover and wiggle gently on both sides until you can remove the cover. Please choose LED lamps that are low profile as there is not that much space for long lights.
Take in account that you will not get the even distribution of light that you get on the cover with the incandescent lights. What I recommend is that you choose a LED that has a lens in the front and no side LEDs in that way you will only get one even point of light.
Also the dimming effect when the light goes off could be a little choppy. Expect some flickering at the last second
Load space lamp
Type C10W
Base SV8.5-8
Consumption 10w
As known as Festoon 42mm or 6411
Replace with Festoon 42 mm LED white
Insert a small flat head screw driver on the far side and gently wiggle one side until free. Most of the Festoon type LED lights only have LED chips on one side. Keep in mind that you can rotate the light a little to point to the center on the cargo bay so you will get a more focus light
Side repeater lights
Type WY5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 amber or 168
Replace with T10 LED amber
I will not say much about this bulb as I have not seen any way to change it. If you have been patient enough to get this far and you have any idea on how to change those bulbs please let me know,
Perhaps the only thing to mention is that you need to get a very low profile T10 lamp since it does not seems to be a lot of space for anything bigger than the normal W5W
I hope that you are still awake at this point. If you have any idea on where the mentioned relay is or how to open the side mirror housing please let me know
I will update as soon as I get more information
Being an EV whatever you can save in power contributes to the range of the battery. Yes I know that the watt consumption of the lights in the car is minimal against to the total consumption of the HV electric motor and can be ignored but, every watt counts. The headlights are 120 watts (60 w each) over a period of 4 hours they consume almost half of a KW and that is not taking in account the other lights like fog lights (30 w) rear lights (30 w) and others
The second reason, and probably the main reason, to change the lights has to do with the heat they produce and this applicable to ICE vehicles as well. Most of the bases and housings for the lights are made of plastics and even when they are calculated to withstand the high temperature produced by the bulbs with the time they can degrade and cause color variations on the refractive lenses and hardening of the base material. We all have seen the yellowish shade that the cabin lights gets on old cars due to the high temperature of the light bulb. The lower the temperature the longer the life of the plastic. Just touch the exterior of any housing after it has been on for a while and you will feel that they get hot.
The third reason has to do with the cabling on the wire harnesses. The cabling on modern cars is calculated to handle exactly the amperes that the application requires. No less no more just to comply with the security standard. With the time the insulation on the cable degrades. This happens to any cable automotive or not, so the less current you pass thru the cable the longer the life expectancy.
All these reasons can be considered superfluous, because all those effects will take years to takeover but as a general rule I want to avoid them in the future for me of for the next owner of this car.
Anyway. I wanted to share my experience so if you are considering to change some of the bulbs in your car you can take in account several points. So lets start with some comments about every bulb in the car.
Headlamps
Type HB3LL
Base P20d 90°
Consumption 60w each
Also known as 9005 or only HB3 (if you read the manual you will find the the designation of “LL” has to do with the life expectancy of the halogen lamp but not with the shape of the lamp
Replace with HB3 LEDs
There has been a lot of discussions on the forum about changing the headlamps so I will not comment that much. Also there are several YouTube videos on the matter. Besides that I have not received mine since they are on the mail. Just to mention that I decided to go for the Auxbeam F16-plus. I will post more about these lamps once I change them in my car
Please take in account that you need to consider the form factor of the replacement since not all the lights will fit the housing. Also not all the replacements are legal on all countries so you need to consult your dealer to see if you can do the change
Front direction indicators
Type PY21W
Base BAU15S
Consumption 21w each
As known as BAU15S or 7507
Replace with BAU15S LED amber
They are located in the same housing as the main headlamps at the front. Just turn a quarter of turn the base and pull. Take in account that the base BAU15S is very similar to BA15S. The difference will be that the BAU15S has a deviation of 30 degrees on the position on the side pins on the base (the two little pins on each side of the cylinder base) the BA15S are straight with the center of the base cylinder.
So far as I can see on all the bulbs there is no CANBUS control. CANBUS is used for the lights on some cars to report if a bulb is burn and needs to be replaced. It seems that this is not the case for the MG ZS EV. Please correct me if I am wrong
But if you change the turn signal bulbs you will get want some people refers to hyper flashing. That is basically a more rapid flashing of the turn signals. That effect is usually caused because the internal resistance of the LED light is different to the regular incandescent bulbs.
Usually this error is corrected by using load resistors in parallel to the LED lights so they can compensate the resistance on the flash relay. If you use that method the lights will work but in general it defeats the idea of using LED light since you will not be consuming less power just dissipating it on the load resistors, and also you have to modify the cabling and drill holes on your car.
The second method, and less intrusive, is to change the stock flash relay for a solid state relay so it will not be affected by the resistance on the LEDs. They are usually trade as LED ready relays.
That being said, I change all 4 direction indicators (front and back) and I get the hyper flashing. Since I do not want to consume watts on heat on load resistors I started looking for the flash relay to see if it can be replaced, but I was not able to find it. Actually the clicking sound comes from the driver side speaker on the car. It seems that the clicking sound if just a fake audio indication for the driver.
So does anybody knows where is the relay (if any) that controls those lights? Has anybody done the change successfully?. If so any help will be greatly appreciated.
Rear side lights
Type W5W
Base W2.1×9.5d
Consumption 5w each (20 w total)
As known as T10 or 168
Replace with T10 LED white
There are 2 bulbs on the housing located on the tail gate on each side. Obliviously the idea will be to replace them with the same type of LED so you do not get variations on the intensity. I highly recommend to use LEDs that have all around chips and not only on the front since this light is mean to spread so it looks like a continuous light. If you get the ones with only a lens on the front you will get spots of light.
To remove the tail gate housing you do not need to remove the side cover on the housing. Actually I will recommend not to remove it since is held by plastic clips and there is a high risk to break them. To remove the housing open the tail gate, on each side there is a plastic cover on the interior face. You can remove those covers introducing a flat head screw driver on the slot on the cover. I recommend that you use a plastic tool to remove covers. They are a few bucks (or few quids should I say) for the set on Amazon or Ebay otherwise wrap some electrician tape around the head of a flat head screw driver so you avoid any scratch on the plastic finish.
You will get access to the back of the housing and you will see 3 small nuts. Remove them and wiggle the housing, the plastic side cover will not interfere when you pull out the housing. You will find two small bases at each side where you will replace the bulbs
Reverse lights
Type W16W
Base W2.1×9.5d
Consumption 15w each
As known as T15 or 921
Replace with T15 LED white
They are located also on the tail gate housing. Follow the procedure described before to remove the housing.
The W5W (T10) and the W16W (T15) have the same base the difference is that the actual bulb is bigger. So you can replace those lights with T10 lights but the need to be high intensity. The size of T15 LED lights is very similar to the T10s the only difference is that the T15s will have almost double the quantity of LED chips, hence double or triple the light.
I recommend that you use the highest intensity light that you can get as the reverse light reflector is very small. Also they should be all around LEDs so you use the reflector in the housing.
Rear fog lights
Type P21W
Base BA15s
Consumption 21w each
Also known as BA15S or 1156
Replace with BA15S LED white
We have to thank our friends at SAIC for the acrobatics on this one. I don’t see any way to remove the housing other than removing the whole rear bumper. I guess the designer at this point was tired of trying clever ways to give easy access to the user to change the bulbs. Please let me know if you find a way
So in order to change those bulbs you have to lay in your back near to the position of the housing, look inside the rear bumper and you will see the red housing. You will see in the middle of the housing a gray base. You have to introduce your arm (there is a round cut out in the bumper) so you can reach the base and turn it a quarter and pull the base to change the bulb.
BTW in my car they were really stuck because the rubber o-ring to prevent water to get into the housing. I recommend that you apply a little silicon grease around the o-ring so is not that hard to put it back in place.
Thankfully these ones are BA15S base so it does not matter how you place the light it will fit. These lights have to be all around LEDs chips since they are on vertical position
Stop Lights
Type W21/5W
Base W3×16q
Consumption 21+5w each
As know as T20 dual or 7443
Replace with T20 dual LED white.
Please note that if you ask for T20s they will usually will not have two levels of light. You have to make sure the LED that you purchase has two level lights, one high when you press to stop pedal and another low that stays on.
They are located on the rear chassis housing. To access the hex screws that hold the housing on the main chassis you need to remove a cover that is located among the weather rubber seal of the tail gate and the housing. The cover is hold by plastic clips that attach to the housing you just need to pull them. Be very careful when you put them back because they are not very good quality to say the least, and you can break one of the clips.
After you remove the covers you will see the hex screws. You remove them and the wiggle the whole housing to pull it out. There is no other screws or nuts, there is just plastic fasteners and plastic pins that keep the housing in position. The bulb is located on the center of the housing and is bigger than the one on the side.
License plate lights
Type W5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 or 168
Replace with T10 LED white
They are located at each side of the rear camera. Just insert a flat head screw driver on the slot on the transparent housing on the side near to the camera and pull one side. Please note that in order to put it back you have to insert the side with the two hooks first.
Try to replace with LED that will provide as much even distribution of light as possible otherwise you will get spots of light on your license plate
Rear direction indicators
Type WY16W
Base W2.1×9.5d
Consumption 15w each
As known as T15 or 921NA
Replace with T15 LED amber
Located at the rear chassis housing. Follow the procedure described before and the light will be the smaller base on the housing. They will present the same issue that I described on the front direction indicators.
Interior lamp
Type W5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 or 168
Replace with T10 LED white
Insert a small flat head screw driver on the side of the white cover and wiggle gently on both sides until you can remove the cover. Please choose LED lamps that are low profile as there is not that much space for long lights.
Take in account that you will not get the even distribution of light that you get on the cover with the incandescent lights. What I recommend is that you choose a LED that has a lens in the front and no side LEDs in that way you will only get one even point of light.
Also the dimming effect when the light goes off could be a little choppy. Expect some flickering at the last second
Load space lamp
Type C10W
Base SV8.5-8
Consumption 10w
As known as Festoon 42mm or 6411
Replace with Festoon 42 mm LED white
Insert a small flat head screw driver on the far side and gently wiggle one side until free. Most of the Festoon type LED lights only have LED chips on one side. Keep in mind that you can rotate the light a little to point to the center on the cargo bay so you will get a more focus light
Side repeater lights
Type WY5W
Base W2.1×9.5d
Consumption 5w each
As known as T10 amber or 168
Replace with T10 LED amber
I will not say much about this bulb as I have not seen any way to change it. If you have been patient enough to get this far and you have any idea on how to change those bulbs please let me know,
Perhaps the only thing to mention is that you need to get a very low profile T10 lamp since it does not seems to be a lot of space for anything bigger than the normal W5W
I hope that you are still awake at this point. If you have any idea on where the mentioned relay is or how to open the side mirror housing please let me know
I will update as soon as I get more information
