Technical Yet another lighting problem! (2010 X250)

[mprowe]

Hello All,

May I ask for some help/ideas? The vehicle is a 2010 X250 based motor home (or though I don't think it is a convertors' issue?).

Symptoms: Dashboard "Side Lights" warning light is on. Stalk unit (H005) turned to first click (side lights) do not bring in any lights.

Investigations: Using MultiECUscan (v4.0 Registered).

I note these error codes from the body computer:​

1. B1009 - Side lights on Left ...
2. B100A - Side lights on Right ...
3. B1016 - Brake lights.

Clear error codes and using the Body Computer | Actuate functions, cycle through each light sub-circuit - left side light, right side, brake, fog etc.​

All lights are turned on/off/on/off as expected. The above three error codes are renewed following this exercise.​

Conclusion - no wiring or bulb problems.​

​

Repeating the above, in differing combinations, I note that, BOTH the B1009 & B100A are triggered after either actuating the NS or OS side lights via MultuECUscan.​

​

From the above, I am tending to think that there is probably a common failure point towards or in the body computer.
While (I think) I understand how the lights are commanded on, the flow path to detect a fault is still a mystery to me. So my question to you all is:

Does the body computer (in response to the side lights ON command), turn on each sub-circuit one at a time (left, right etc) to measure the expected current in that circuit? Then, if that value is outside defined limits (too high or too low) turn it OFF again (and keep it off)?

OR... if you can point me directly at a test to solve this problem - that would be even better

Best regards, M.

 

[Anthony489]

Hi mprowe

The body computer monitors the current drawn by the bulbs, and if it's too high or too low for some reason it will throw an error and may turn them off as a protection measure. I suggest you check that the bulbs are the correct wattage, don't have blackened glass and have good connections. Any twin filament bulbs must be in the right way round (yes I know they have staggered pegs but I have still found ones forced in the wrong way !) It's also worth checking the multi-way connectors to the rear light clusters (if your conversion still uses these) to make sure they don't have any tarnished connections. If the common earth is bad or open circuit , you can get tail lights finding a current return back through the brake lights or indicators instead, which will play havoc with the monitoring.

 

[Crossingkeeper]

To follow on from Anthony's very helpful reply my van, which is of a similar age, has high level marker lights which are presumably somehow linked to the side light circuits by the converter. The front ones are set into the over-cab moulding and are quite difficult to see from ground level (and very vulnerable to water ingress!)