Error messages abound, parking brake stuck, and a 5000 lawn ornament. HELP!

[NewbyMaybe]

What I'm asking is if the pads wiggle a little when you tap them with a screwdriver or wrench. If corroded they sometimes can't move.

 

[Gtech]

Yeah - it's not even _TRYING_. Replacing the calipers tomorrow too. The calipers respond to power on pins 1 and 4 to engage/disengage.... I feel like a kid in the 80's replacing parts by guessing. What's the point in having the advanced diagnostics "toolbox" if you can't use it!! LOL

Last week I had an issue with parking calipers and getting car in neutral or park was no issue even with connector removed from parking brake actuator. Car drove fine for 1 week with left rear connector unplugged.

If you disconnect EPB module don't think the issue lies in the calipers maybe another component is shorting your Chassis CAN maybe LDU? You tried disconnecting LV LDU connector? Did you tried measuring it if signal Chassis CAN is healthy? Can you please post a summary of the situation and post service errors?

 

[Hank42]

Last week I had an issue with parking calipers and getting car in neutral or park was no issue even with connector removed from parking brake actuator. Car drove fine for 1 week with left rear connector unplugged.

If you disconnect EPB module don't think the issue lies in the calipers maybe another component is shorting your Chassis CAN maybe LDU? You tried disconnecting LV LDU connector? Did you tried measuring it if signal Chassis CAN is healthy? Can you please post a summary of the situation and post service errors?

I agree with your theory that something else might be sorting the Chassis CAN bus - I have an Arduino CAN interface I used with a program I wrote to issue a CAN reset for intermittent HV isolation faults a while back(before I fixed the root cause) - I guess I'll repurpose that and see what's up. Maybe I can use it to tell the car to go into "Park".
And good suggestion on pulling the LDU - will crawl under and do that too.

 

[Hank42]

What I'm asking is if the pads wiggle a little when you tap them with a screwdriver or wrench. If corroded they sometimes can't move.

They, they engage/disengage just fine when I apply power - free enough that the rotor moves cleanly when disengaged and locked tight when engaged. They do wiggle with a screwdriver when disengaged.

 

[GonePlaid]

No TPMS codes that I found, everything I've gotten from the computer is posted above. 06/13 on the VIN sticker.

I know about the service manual access - and I did find a ground on both sides of the front frame rails, both seem solid and clean. No evidence of any corrosion (I did not disassemble them) and they were both VERY tight. I'll have to look for that CAN junction area, but I didn't see anything in the front that looked damaged or out of place, at least with a quick look around.

Only thing I DID notice that I now know needs attention - the condensation drain hose is aimed straight down behind the penthouse, it would be draining right onto the top of the pack. Not a fan of that but I don't think it is involved.

The first indication of any issue was last week, my sister gets in to drive to work and it is error message city, but at that point it DID still move. Damn parking brake could have just stayed loose, instead it locked her out of the car (b/c it thought it was driving when it was in neutral instead) and finally timed out and went to sleep around 40 minutes after the key was removed from the area. It's been all day and the damn thing is still stuck in neutral (won't shift at all) and the primary error is "Parking brake FAULT" on the dash - while it is beepbeepbeep CONSTANTLY about the other 18 errors. Hating this so much right now b/c there's no ability to do ANYTHING with it. If the windows weren't open, it would be completely locked up b/c it thinks it is driving!

 

[Hank42]

UPDATE: Thanks @Gtech for suggesting a CAN bus checkout - I was so focused on checking the parts of the car I was actually working on/repairing - certain in my mind that in re-assembly, I caused the issue.
I Isolated the Can bus from the rest of the car by disconnecting X976 under the rear seat leaving only the TPMS and EPB ECU connected to the rear side of the harness.

Testing on pins 5&6 on the front side of the harness resulted in 120ohms. On the back side, 8 ohms - indicative of a problem.
Unplugging the EPB (in the trunk) still tested 8 ohms.
Unplugging X140 - the TPMS located under the aero shield resulted in open on 5&6(that's good!)

Reconnecting the EPB brought me back to ~120 ohms across 5&6.

And reconnecting X976 but leaving the TPMS disconnected resulted in the car powering up, able to shift gears, parking brake works, and IC powering up.

The location of the TPMS is questionable - on my car it is mounted on the bottom of the DU cradle cross-member - easily damaged by road debris. Mine looks a little beat up, but does not appear to be significantly damaged.

Either way, it caused a short on the CAN bus resulting in all sorts of headaches. I hope this might help someone else down the line - I would never have suspected this to be the culprit based on the errors and symptoms, although, the moment I realized the CAN bus was faulted, it all makes more sense now. Glad it's not the harness! Thanks @Gtech !

 

[Gtech]

UPDATE: Thanks @Gtech for suggesting a CAN bus checkout - I was so focused on checking the parts of the car I was actually working on/repairing - certain in my mind that in re-assembly, I caused the issue.
I Isolated the Can bus from the rest of the car by disconnecting X976 under the rear seat leaving only the TPMS and EPB ECU connected to the rear side of the harness.
View attachment 1054643


Testing on pins 5&6 on the front side of the harness resulted in 120ohms. On the back side, 8 ohms - indicative of a problem.
Unplugging the EPB (in the trunk) still tested 8 ohms.
Unplugging X140 - the TPMS located under the aero shield resulted in open on 5&6(that's good!)
View attachment 1054644
Reconnecting the EPB brought me back to ~120 ohms across 5&6.

And reconnecting X976 but leaving the TPMS disconnected resulted in the car powering up, able to shift gears, parking brake works, and IC powering up.

The location of the TPMS is questionable - on my car it is mounted on the bottom of the DU cradle cross-member - easily damaged by road debris. Mine looks a little beat up, but does not appear to be significantly damaged. View attachment 1054645

Either way, it caused a short on the CAN bus resulting in all sorts of headaches. I hope this might help someone else down the line - I would never have suspected this to be the culprit based on the errors and symptoms, although, the moment I realized the CAN bus was faulted, it all makes more sense now. Glad it's not the harness! Thanks @Gtech !

Nice troubleshooting, glad you solved the issue, it CAN (lol) be tricky when other parts break right after you did a big repair.

Continental TPMS is located inside cabin

 

[Hank42]

Nice troubleshooting, glad you solved the issue, it CAN (lol) be tricky when other parts break right after you did a big repair.

Continental TPMS is located inside cabin

I'm turning this into an opportunity to upgrade to the conti tpms
[Luv the pun]