JudsonV

So I had my rear hatch not latch completely and it killed my battery overnight. After boosting the R I got a slew of errors. I guess Merc’s get fussy when a battery goes dead or is replaced. I have an MB Icarsoft II and most of them cleared fine but I was playing around in the diagnostic menu and turned the road test mode and now stuck in the diagnostic rig test. Got the rig test error message along with the abs light and tire pressure monitor not available errors. When I check the code on the EPS module it shows road test mode active. Have found half a dozen different directions to complete the road test. So here’s the steps I take:

1: car on flat ground with wheels straight with car in park
2: break pushed and move shifter to neutral
3: release the break so in neutral with foot off the break
4: press the esp off button and esp light starts to flash
5: as long you are in neutral it will go from flashing to solid
6: break press and move shifter to drive, foot off the break and accelerate to 10km/h
7: once up to speed I turn the wheel to the right, more than 90 degrees and less than 180 degrees effectively doing a U-turn.
8: this is the step I never get too. According to sources once you complete the half circle the esp light should go from solid back to flashing and that’s when you’re supposed to come to a stop and put the car in neutral

it did flash once for me when I was turning and I got all excited I got to that step and then I think I screwed up the next step to compete the test. Have never got to flash again while turning.

any suggestions or is there anything I’m doing incorrectly?

Tsumi

If you can't find anything specific to the R class, try W164 and X164 forums. Mechanically and electrically, the 164 and 251 series are the same.

JudsonV

Well manage to finally complete the road test. I went out today and took to the store to run some errands and decided id go to the corner of the parking lot where I had lots of space and give it a try. Probably tried 8 or 9 times and no luck. I could never get the EPS light to go from solid back to flashing while completing the turning procedure. Got frustrated and headed home. Close to home, I thought about just trying it on a quiet street near my house. So I came to a stop on a street next to mine, put it in neutral, pressed the ESP off switch to start the test and got it flashing and then proceeded to start driving and made the 90 degree turn onto my street, and sure enough, it went from solid to flashing indicating I had completed the turning part of the test. I just simply pulled into my driveway at that point and used the break to a stop and put it in neutral from drive and let off the break and the lights went out. I'm not kidding when I say I probably attempted to do the road test 30 times in an empty parking lot and could never complete it. The first time just trying it in a quiet neighborhood and just completing a turn onto a side street was the key to getting the test completed.So yeah best advice if your not getting through the steps, just follow the steps listed aboved but just do it on a side street and the only turn you need to complete during the test is a simple left hand or right hand turn onto a perpendicular to complete a 90 degree turn.