phoenix_iii

edit: 2007 W164 ML350
edit2 1/16/18
Hi MBWorld,

I had a 4 wire trailer harness installed by an independent shop 2 or 3 years ago. I told them not to use vampire taps and to splice and solder. They promised they would. I check the work, and it's vampire taps. I made them give me a 5 year warranty on the work.

Fast forward to today. Had them rewire (solder/heatshrink). Everything is normal except for the passenger turn signal mirror, and I also noticed that the courtesy light up lamp (Mirror housing light that shoots down to running board) does NOT light up either on un-lock (the turn signal does illuminate on lock/unlock).

I also have some intermittent issues with the passenger side rear tail lamp and brake light, but after cleaning the connections it seems to have abated.

I think I read it is possible for the wiring to get damaged from the power folding mirrors, is this possible to get the no turn signal but still light/flash on lock?

I've been having issues with inconsistent rear turn signal, rear brake lights being 'out'. All of this on the same side (right side) they hacked for the harness. Typically reseating the rear right lamp bulbs fixes the problem (it could just be corrossion), but this one I can't shake: Right Turn signal Mirror lights do not blink unless locking or unlocking. Hazard, turn signal stalk, does not activate it .I do have the warning and fast blinker sound in the HUD.

TL;DR - Right Turn Signal (Mirror) error, does not blink with Hazard or Turn stalk, DOES FLASH (all LEDs) on Lock (or is it unlock?).

Can I blame the trailer installation some-how? Could it be related? Could it have stressed out the rear SAM? SAM is dry/no signs of light leakage.

flybd5

You're on the wrong forum. You'll probably have better luck asking in the correct one, here:

https://mbworld.org/forums/c-class-w204-83/

phoenix_iii

updated thread. I'm in the right place I think.

Maj. Dundee

You are on the wrong forum.

Andrew Mayzen

I had the same issue plus more with a Hayman Reece installation on my ML320CDI. The Hayman Reece ECM plugs into the cable from the drivers side (RHD)Tail light Plug and has a cable that then goes to the light plug. I took the unit out and things worked fine. It was water damaged from the tail light letting in water from the top area seal. If you park nose down in the rain, if leaking it will run in and fill the area behind the tail light. The other issue is the tracks the globe holders make contact with corrode, MB makes a bypass unit you splice in if req, or just be done with it and buy led tail lights off ebay for $300. Remember that these cars run a bus wiring system and when a momentary break in contact to light a lamp happens the car will disable that circuit and make another light take its place, taillights become brake lights, reverse lights become blinkers etc. You need to turn off the ignition totally to reset and start fault finding again. Another thing to be mindful of is that in that same area of the fuse box and taillight there is a black box that controls all these electricals ie the SAM or signal acquisition module which costs $2000 in Australia from the Stealership or $1100
as a grey import from the states. It will die when it gets wet, things like no tailgate lock\lift and no lights working will happen. They also need to be programed with your accessories fitted when replaced. My replacement SAM was a superseded model that incorporated a trailer ECM.

flybd5

Then please update your profile to show that you also own this vehicle. You have a 5-year warranty, which you asked for instead of demanding the shop redo the work as you required. Time to take it back to that shop. If the shop verifies the installation is still good you need to come back with a list of the codes your car is reporting.

phoenix_iii

*profile updated as per flybd5*

Thank you Andrew. So, it is 100% probable that the vampire taps in the rear right wiring could be causing confusion or issues on the BUS/communication system the car uses.

There is no (major anyway) indication of moisture or wetness around the tail light. I am going to inspect it further. I just did not want to deal with this shop again, but I can do so with more confidence if what I am postulating is true.

Is there any particular language I should use (about the CAN/BUS) :P

My particular issue is the mirror turn signal error on the right side. I know the wiring is 'fine' since the thing blinks on lock (or is it unlock), but I've read about the folding mirrors damaging the wiring eventually. Is that worth pursuing? Is it different signal wires for lock/unlock vs. turn signal?

dfghhgfd

For what it's worth, I have an '06 ML500 and had a problem with the left blinker continually going out with the corresponding warning on the dash. Every time I checked the bulb it was in fact good. (I don't have any trailer lighting installed) Reseating bulbs, replacing bulbs and contact cleaner worked temporarily, but it would continue to not work after some time. Finally I pulled the taillight units and thoroughly cleaned with a brass wire brush and contact cleaner and finally sprayed with contact protectant the contact plate on the back of the fixtures where the bulbs actually make contact for power, and finally the problem went away. Before I started it didn't look like there was any corrosion on the contact plate, but obviously there was.
That's my 2 cents!

phoenix_iii

Any other feedback?

flybd5

Did you take it back to the company that did the wiring install with the cheap vampire taps?

phoenix_iii

Appointment is scheduled. Just wanted to have forum level knowledge if they try and BS me.

flybd5

We can't guess if they are trying to BS you unless you tell us what they say to you...

phoenix_iii

Updating here and original thread.

Had them rewire (solder/heatshrink). Everything is normal except for the passenger turn signal mirror, and I also noticed that the courtesy light up lamp (Mirror housing light that shoots down to running board) does NOT light up either on un-lock (the turn signal does illuminate on lock/unlock).

I also have some intermittent issues with the passenger side rear tail lamp and brake light, but after cleaning the connections it seems to have abated.

I think I read it is possible for the wiring to get damaged from the power folding mirrors, is this possible to get the no turn signal but still light/flash on lock?

flybd5

Only thing I can think of is a damaged SAM. You'll need to read any fault codes from the car to troubleshoot that.

phoenix_iii

Broken wire from all the power folding. Fixed now.