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Hi all,
This issue is ONLY when the car is warm, and I go to drive it again before it’s cooled down. When it sits overnight, it’s fine.
the car doesn’t respond to the fob, I go inside manually and it won’t go into accessory mode or start mode. No electronics turn on.
All the grounds are clean, Bcm looks fine; haven’t tested internally, fuse box pins and all look fine
it has a class 2 data link code and a communication CAN bus error.
where should I look or what should I do next?
The RCDLR is on the low speed class 2 serial data bus...that module is needed for the FOB to work and also for the car to start...if that single wire class 2 is shorted to either power or ground you will have comm issues...you can't diagnose this by this or that "looks" fine...you MUST check...do you have a DMM and know how to use it ??...you will need to take a voltage and resistance check at terminal 2 at the DLC...if not seek out an auto electric shop in your area.
The RCDLR is on the low speed class 2 serial data bus...that module is needed for the FOB to work and also for the car to start...if that single wire class 2 is shorted to either power or ground you will have comm issues...you can't diagnose this by this or that "looks" fine...you MUST check...do you have a DMM and know how to use it ??...you will need to take a voltage and resistance check at terminal 2 at the DLC...if not seek out an auto electric shop in your area.
How do you test it? What do you test for? Does it have to be plugged in, testing through a connector, a different connector…
Well let's just start with terminal 2 at the DLC (OBD2 port)...with the battery disconnected checking between terminal 2 and terminal 4 which is chassis ground you should see around 4.5 kOhms...4,523 ohms which I see on my 2008....if you had ignition function you can check voltage which will be fluctuating with ignition ON between 0.2 to 0.7 volts...with a labscope you should see a 0-7 volt square wave....humor me and check fuse 11 in the under hood box...ECM/TCM/EASY KEY...and don't check the fuse VISUALLY...check with a 12 volt test light !!...is this part of the issue you posted a few days ago ??...TRY TO KEEP EVERYTHING IN ONE THREAD !!
Well let's just start with terminal 2 at the DLC (OBD2 port)...with the battery disconnected checking between terminal 2 and terminal 4 which is chassis ground you should see around 4.5 kOhms...4,523 ohms which I see on my 2008....if you had ignition function you can check voltage which will be fluctuating with ignition ON between 0.2 to 0.7 volts...with a labscope you should see a 0-7 volt square wave....humor me and check fuse 11 in the under hood box...ECM/TCM/EASY KEY...and don't check the fuse VISUALLY...check with a 12 volt test light !!...is this part of the issue you posted a few days ago ??...TRY TO KEEP EVERYTHING IN ONE THREAD !!
this was with battery disconnected and pins 2 and 4 at the DLC.
battery on and in ignition mode it fluctuated from 0.1 to as high as 2.8 volts. Most of the time it was .2-1.0 volts
07 Z06 no electrical power
