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BGarrett
08-09-2013, 02:50 PM
Guys
My 04 NAFTA will occasionally show P1926 (CAN Communication is Faulty) on the EWM (Electronic selector lever module). Anyone know if this means I have a bad Gear Shift assembly on the dash, or does it more likely point to a bad sensor or wiring somewhere else on the van? Another possibly related symptom, the ODBII communications apparently doesn't work on my van. A Scangauge II or any other ODBII scanner I've tried won't connect to the van, I have to use a Sprinter specific scanner to even read the codes. Is there any information out there about how to diagnose CAN buss comm issues? I know that on industrial busses, sometimes you have to disconnect parts of the buss to isolate the problem. :thinking:

Aqua Puttana
08-09-2013, 05:42 PM
Guys
...A Scangauge II or any other ODBII scanner I've tried won't connect to the van, I have to use a Sprinter specific scanner to even read the codes... :thinking:
Most every time we have heard similar symptoms the problem has been traced to an aftermarket radio or other unit such as a commercial monitoring device being improperly connected to the CAN bus.

The CAN B is used for OBDII communication. CAN C is used for engine/transmission so if the CAN A only is affected the engine is still able to operate.

If you have an aftermarket radio or any other devices I would first double check the wiring on those. Good luck. vic

BGarrett
08-10-2013, 12:19 PM
Thanks, I put in an aftermarket radio shortly after I got the van. is there anything in particular i need to look at in the wiring? I can't remember if I had a wiring kit or I just spliced the wiring together, but my antenna definitely isn't working well. I'll pull it out first opportunity and look it over carefully.

Aqua Puttana
08-10-2013, 01:41 PM
I suspect that many times the replacement radio wires get connected to the speed sensor wire. On the OEM radio the volume is supposed to vary based upon vehicle speed. I never noticed that working on my POS OEM Sound 10. The speed sensor wire should not be connected for most (all?) aftermarket units.

The Sprinter amplified antenna needs to have a 12 vdc supply to power the amplifier electronics. vic

Thanks, I put in an aftermarket radio shortly after I got the van. ...