[tallatghazi]

Hi,
Visually all external lamps/bulbs are working perfectly fine except 2 reverse white lights. Bulbs are fine but there is no 12v in left and right wire holders. image are attached for a closer look

Without touching anything else, when I start the engine only then I receive the message "Lamp Defective Check Lamps!".
Is this message appearing due to reverse light wiring issue? if yes then my point is that unless I am not putting the car in reverse gear it should not throw this message.

Kindly help me with this error message.

Thanks!
THG

 

[Check Codes]

You'd only get the message as the circuit comes active.

You don't mention where you are (please click user cp and edit details so you can add your location to your profile, as here, often it's useful information when you're seeking assistance) but if you are in a place that has DRL, it's likely to be a city light or headlight, or, anywhere, a brake lamp bulb (since you're likely to be stepping on the brake when you start the car). There is a kind of checklist in the stickies for at least tracing the right circuit, perhaps that will help.

Not seeing any referenced images...sorry.

Good luck.

 

[tallatghazi]

You'd only get the message as the circuit comes active.

You don't mention where you are (please click user cp and edit details so you can add your location to your profile, as here, often it's useful information when you're seeking assistance) but if you are in a place that has DRL, it's likely to be a city light or headlight, or, anywhere, a brake lamp bulb (since you're likely to be stepping on the brake when you start the car). There is a kind of checklist in the stickies for at least tracing the right circuit, perhaps that will help.

Not seeing any referenced images...sorry.

Good luck.

Hi,
Thanks for your quick reply, I am deployed in a rural area and there is no good workshop near by but as I have mentioned, I have strongly observed that I only sit inside my w210, close the door, did not touch anything or press the brake pedal ( i have done this experiment so many times even without engaging the handbrake), just insert the key and turn it to position-2, (no warning message yet), but when I start the engine the warning message appears, after like 1.5 seconds.

(Please check the images)

Thanks!
THG

 

[tibu]

Hi,
Thanks for your quick reply, I am deployed in a rural area and there is no good workshop near by but as I have mentioned, I have strongly observed that I only sit inside my w210, close the door, did not touch anything or press the brake pedal ( i have done this experiment so many times even without engaging the handbrake), just insert the key and turn it to position-2, (no warning message yet), but when I start the engine the warning message appears, after like 1.5 seconds.

(Please check the images)

Thanks!
THG

did you ever find a fix to the issue ? i am currently experiencing exactly the same issue, and im really at a loss at this point

 

[mrboca]

did you ever find a fix to the issue ? i am currently experiencing exactly the same issue, and im really at a loss at this point

What is the year and model of the car ? At what exactly is the problem ? No reverse lights ? Defective lamp message too without pressing / turning on anything ?

 

[tibu]

What is the year and model of the car ? At what exactly is the problem ? No reverse lights ? Defective lamp message too without pressing / turning on anything ?

1998 w210 e300td sedan, the reverse lights dont come on when reversing.. i found a drawing that shows where the plug that goes from the tail-lights to the shifter with the 2 wires ( gray and green/ gray ) .. one is power in, the other one is power out .. i tested them both and they both actually have voltage (12v), was hoping for one of them to be 0 because thats an easy fix .. anyway, then i focus on the rear end, i unplugged the socket from the tail-light that houses the reverse light ( on the trunk lid ) and tested the bulb, bulbholder and the wires going to the connector... the bulb and bulbholder and everything related to it seems to be fine.. but once i took the meter to the wires that are in the plug, it looks like the reverse light wire is still showing 0 .. so i honestly dont know how to keep diagnosing the issue

 

[mrboca]

Hello

I believe you are looking at the wrong place... The power to the reverse lights is supplied and monitored by the Illumination Control Module (ICM), aka Light Switch Module, not by the reverse switch in the shifter.

The wires that go to the reverse contacts in the shifter are just sense circuits. Basically ICM send 12V to the switch and if it receives 12V, it deems that the reverse light switch is closed, and then supplies power to the reverse lights.

You need to first check the reverse light (back-up light) fuse at the dash driver side fuse panel which is located just left of the headlight switch. You need to remove the lid and locate the fuse. You should have a fuse listing insert to tell you which fuse is which.

 

[tibu]

Hello

I believe you are looking at the wrong place... The power to the reverse lights is supplied and monitored by the Illumination Control Module (ICM), aka Light Switch Module, not by the reverse switch in the shifter.

The wires that go to the reverse contacts in the shifter are just sense circuits. Basically ICM send 12V to the switch and if it receives 12V, it deems that the reverse light switch is closed, and then supplies power to the reverse lights.

You need to first check the reverse light (back-up light) fuse at the dash driver side fuse panel which is located just left of the headlight switch. You need to remove the lid and locate the fuse. You should have a fuse listing insert to tell you which fuse is which.

i did also check all the fuses, theyre fine .. but how do i go about checking if the ICM is in working order ?

 

[mrboca]

You need to check if the wire from reverse switch in the shifter to the ICM is broken.

Does your passenger mirror dip (point downwards) when the mirror switch is selecting the passenger side mirror, and you shift to reverse gear with engine running ?

Also check voltage on the reverse light fuse. Sometimes the holders go bad (corroded / loose) in that area.

Also check the resistance between chassis ground and each of the supply wires where the reverse lamps are. One of the wires may have a short to ground.

Do you have the defective bulb message as soon as you put the gear in reverse ?

 

[tibu]

You need to check if the wire from reverse switch in the shifter to the ICM is broken.

Does your passenger mirror dip (point downwards) when the mirror switch is selecting the passenger side mirror, and you shift to reverse gear with engine running ?

Also check voltage on the reverse light fuse. Sometimes the holders go bad (corroded / loose) in that area.

Also check the resistance between chassis ground and each of the supply wires where the reverse lamps are. One of the wires may have a short to ground.

Do you have the defective bulb message as soon as you put the gear in reverse ?

well the mirror does not dip, the defective bulb message comes on as soon as i turn the ignition on.. dont even have to turn on the lights or put it in reverse.. i try the reverse gear thing when the key is in pos 2.. because im usually alone when diagnosing the issue, so its kind of hard to actually turn the car on and keep running out to check if the lights actually turn on ( obviously )

 

[mrboca]

I assume you did the passenger power window dip test with the passenger mirror is selected at the mirror switch, and with the car is running and gear in reverse.

I suggest you pull the shifter reverse switch connector out and measure the resistance of the reverse switch at the shifter connector when the reverse gear is engaged and when it is not. Voltage measurements are misleading due to bias of the sense circuits. Remember that the reverse switch does not feed the reverse lights, but the ICM does.

 

[Green 300]

Iam also having the same problem except that my reverse is working. I also have the def. lamp message whenever i turn on the car. May I know where the location of the illumination control module.

 

[mrboca]

It is behind the headlight switch. The headlight switch is part of the ICM (and so is the fuse panel at the side of the dashboard).

Is your car equipped with daytime running light system ?

 

[Green 300]

No it doesnt hace day time running lights.
Do i have to try changing the headlight switch if the fuse solution will not work.

 

[mrboca]

I would not replace the ICM till I confirm that it is the defective part. These problems are usually wiring / connector / grounding issues.

Have you noticed that the reverse lights blink once when you start the engine ? Have someone to observe it as you turn the engine on with in Park, feet away from the pedals.

 

[Green 300]

I will check. That would be start at park position, shift to reverse the observe for blinking. Did I get it right? Thank you. Youve been very helpful.

 

[mrboca]

No, don't shift to reverse. Just start the car in park and let someone observe the reverse lights for a single blink. Then put it in reverse, and observe that the reverse lights are working. I understand that your lamp defective light comes on with the engine started in Park with no brake pedal pressing and no external lights turned on.

 

[Green 300]

Thank you. I will do it.

 

[mrboca]

I just edited the last post.

 

[Green 300]

The reverse light is working well. There was no blink on the reverse light upon start of the car. Anu ideas?