Non starting project

[mark kehe]

Sorry for the long first post...

 

So I bought a project 2009 Cayenne S. Not just any project Cayenne but one that was being sold by someone who bought it as a project from someone else who bought it as a project…quality. As best I can tell this car has not run in better part of 5 years with little done to address it. The upside is it only has about 75k miles and is in really pretty nice shape.  

 

I am dealing with a no crank/start condition. I have replaced the battery, gone through the typical wiring area issues in the floorboard. When I put the key in it is recognized by the immobilizer and the steering lock releases (and the dash and radio come on as expected.) I have monitored the live readings in the modules and can see that the brake pedal switch is working, the park/neutral input is reacting and is correct and the KESSY module has the start sequence ready as “yes.” I can see the ignition go to position 2. Yet when I turn the key I get nothing (other than other “relay” sounds from the engine compartment.) 

 

I can jump the starter relay and the engine will fire right up. I checked the continuity in the circuit between the KESSY and the starter relay and don't have any errors . When I monitor voltage on that circuit, I get a momentary blip on start but it immediately drops. 

 

Code wise I'm getting a Gateway 1336 “CAN comfort OFF”, a 0189 “Terminal 50” sporadic from the KESSY. I have three codes on the transfer case (2039, 2033 and 2025) which seem to point at a bad TC motor. I have a 2053 “Transfer box control unit” on the trans control. I have a bad steering angle sensor and a bunch of errors on the headlight modules. Obviously no engine codes as I can't get it to run. (Oh and only the steering wheel controls work for the PCM. Just want to give the complete picture.)

 

I've gone through all the fuses and I'm kind of stuck on where to go next. Seems like it could be a KESSY issue but it also seems a little too narrow of a fault and I have not come across anyone else with the same exact issue. The fact that so many of the sensors/inputs look to be normal (without anything jumping out as obviously “abnormal”) has me a little stumped. Welcome your thoughts..

[mark kehe]

Picture for sympathy... Tires were cracking so I picked up the wheels off FB (plus I was feeling optimistic 😐)

 

[mark kehe]

Bit of an update... Have cleared all the transfer case and transmission codes through the replacement of the TC motor and fixing a bad connection at the drive selection switch.  I still have the Gateway 1336 "CAN comfort OFF" fault along with Stability Management 1826: Steering Angle Sensor, "Terminal 30 Power Supply" fault and an Advanced Weight system 0470 "CAN single wire operation" fault.  While these are persistent (and annoying) I don't see why they would be contributing to my no crank/start state. 

 

I went back and rechecked the trigger signal at the starter relay and I am getting a pulse but it isn't enough to trigger the relay (I have replaced and swapped the relay with a known working one.) Continuity of the wiring between the relay and the KESSY tests good.  The ground of the KESSY module also tests good.  Battery is new and good. I have run the KESSY test in PIWIS and the test sequence confirms the trigger signal but stops with "no response received." I have no faults with the KESSY.  I know there are known issues with the KESSY components associated with the comfort access going bad but this seems like something different.  Any thoughts....