K6 Relay Testing

[tflda29]

Morning All,

I am having trouble with my ML270 2002. The three braking system lights are on. When i start the car and begin to drive the yellow triangle flashes as if looking for or testing something and then a fourth light comes on...epc...i think and the triangle stops flashing.....

I have replaced brake switch and swapped relay K25 with another one but still the fault is there. There was another relay that said it was for ESP/Brake light attenuation...relay K6.....and when i tested it for resistance out of the car it the opposite reading than all the other relays....ie all the others showed 0 and this one showed 1....or vica versa can't remember which way round.

Before i start looking for chaffed wiring or anything else does anyone know if this relay should be set up differently than the others?

thanks
Trevor

 

[andy27168]

Hi,
Have you not checked your wheel speed sensors, as I think this would be my first port of call before checking anything, you maybe able to put a meter on each sensor in turn this "may" highlight if there is a failled one, but I think I would get it hooked up to a diagnostic machine (STAR preferably), and see what the fault codes read.

 

[tflda29]

Hi , yes i have checked the wheel sensors and they all read the same around 1500 ohms. I did notice that the rear nearside one looked fairly new and from an aftermarket supplier....i have only had the car since last August....

I see that Gendan do a Mercedes specific advanced reader for around £400 and wondered if anyone had experience of this......seemingly can read all systems on the ML.

cheers
Trevor