2008 639 Vito SAM problem

[Unkle sam]

Hello MERC community

I’m hoping for some help with my van.
I put a used SAM in with same model numbers expecting plug and play but no joy.
It fixed the indicator headlight problem but now it will not start. It has new warning lights ABS, ESP.
I cleared codes but now my code reader won’t connect to ecu.
I put old Sam back in to see if it would start but no luck.
Any help would be greatly appreciated as I am stuck in a very remote part of Australia.

Thanks for sharing so much information on this platform

 

[M80]

The SAMs are plug and play.
With the replacement, and now the original, causing starting issues it suggests that the issue is elsewhere.
I would go through the steps taken and see if there is something disturbed, accidentally broken, or not plugged back in.

 

[Unkle sam]

Thanks M80
I was inspired by some of your replies and others on this forum to have a go at fixing the problem.
Will the ABS,ESP and engine light be preventing the vehicle from starting until cleared?
And, do I actually need mbstar or some other quality scanner to get back communication with the ECU? Mine is pretty cheap and nasty.
I hope that I can come up with something embarrassing that I’ve forgotten to do which actually fixes the problem and provides some entertainment. I have been pulling plenty of hair out already throughout this ordeal…

 

[M80]

Will the ABS,ESP and engine light be preventing the vehicle from starting until cleared?

I can't see why it would, so no from me.

And, do I actually need mbstar or some other quality scanner to get back communication with the ECU? Mine is pretty cheap and nasty.

Who can say w/o knowing what the cause is.
If I remember on the back of the SAM there are 2 small, and flimsy plugs. One feds the fuse box fan, in your climate of benefit, but no biggy in the short term if broken.
T'other is the canbus, that'll be a green and a green/black. That could / would affect comms.
But you have some functionality, which suggest the canbus is communicating with / from the SAM.

I hope that I can come up with something embarrassing that I’ve forgotten to do which actually fixes the problem and provides some entertainment.

Me too.
Pulling a SAM on these isn't for the ham fisted or overly eager.
The fuse tray has been out, so checking nothing is amiss with that is reasonable. Are the relay's in place?
Then is all that spaghetti beneath. Look for a forgotten plug, or one that hasn't been engaged by it's clip in latch.
You also have the ECU and TCU within that enclosure. Might be worth pulling those heavy duty plugs atop the ECU, again. Look for bent pins inside the ECU top

 

[Unkle sam]

Hello again and thanks for your help M80

I went straight up the hill after work and spent many hours going over everything on the Vito.
So far I discovered with the ignition switched to the on position that I have 2 fuses '6 and 2' that are going to ground.
I also observed intermittent k4 relay clicking which I can't seem to jiggle anything to create consistent reaction with the relay. I have no reception where the vehicle is located so I haven’t researched anything yet but I would really appreciate any help with these findings.
Anyway, it's 1.30am so it's time to count fuses, relays, wiring looms and the odd sheep