v70 is immobalized

[jonesg]

It looks like a main harness fault.
you could try driving around with vida running to monitor the system real time.

when I had ecm faults all over the car it turned out to be the cooling fan for the ecm box, problem was the fuse .

Unfortunately I can’t get the car to start. Starter motor engages, but no fuel (probably due to the immobilizer cutoff).

on mine the immobilizer prevents the starter from cranking the engine.
I think its something else.

[bigern79]

It’s been another week and I’ve made no progress. I did verify that there is no fuel being pumped at all, but I’m not sure if that is due to the immobilizer. Does anyone know if the fuel pump should still prime? I was under the impression that the immobilizer cuts fuel to the rail, but that the pump should still prime. Can anyone confirm?

[bigern79]

Thought I’d give an update and see if anyone has further ideas. I’ve been troubleshooting slowly but surely over email with Xemodex. We discovered today that the ECM is not getting any power. I tested fuse 12 (for the ECM) in the fuse box with the ignition on, but it also showed no voltage and the fuse is intact. It seems as if there is some issue underneath the fuse panel itself, but I’m not totally sure. I’ve tried prying it out of the box as far as I can, but it doesn’t go far with all the wires connected underneath. I don’t see anything that looks frayed, corroded, or out of place. Anyone have ideas on what I’m missing?

[oragex]

Could it be the CEM has lost the key programming and it doesn't recognize the key chip ?
How does the AWD module DEM look like ? Any significant corrosion ? Read at the bottom of the page
https://xemodex.com/us/product/differen ... 749-10-20/

[bigern79]

Could it be the CEM has lost the key programming and it doesn't recognize the key chip ?
How does the AWD module DEM look like ? Any significant corrosion ? Read at the bottom of the page
https://xemodex.com/us/product/differen ... 749-10-20/

I’m pretty positive that the ECM not having power, and thus not existing to the CEM, is the root of the problem. I just can’t figure out where the power loss is stemming from.

I’ve checked and re-checked pretty much every module connection. I haven’t found any corrosion, crimped wires, or anything else. I’ve run CANBUS tests and confirmed that the circuits are complete as well.

[abscate]

Do continuity checks on the power wires to the ECU and check the pins for corrosion, too

[oragex]

I wouldn't be surprised the immobilizer would cut the power to the ECM.

[bigern79]

Copy/paste from a different forum update, but wanted to make sure it was documented here as well in case someone else can learn something...

I'm beyond excited to report that I was able to locate the source of the issue over the weekend! I decided to go back and re-test the CANBUS circuits again, and noticed that the high CANBUS was now reading 120 ohms (after previously testing fine at 60 ohms). I set my multimeter on my dash and began moving/shaking the ECM harness and noticed that the ohms kept switching from 60 to 120. I started gently tugging on the wires in the A harness, and low and behold one little guy slid right out! The tough part was that I had checked this harness 20 times before, but could not see any issues where the wiring didn't look and feel solid.



When the clutch position sensor was added as part of the manual swap and wired into the harness, the pin that was used was apparently too small. Seems like it was just loose enough that moving the car around would cause it to connect and disconnect, explaining why it was intermittent at first. I was able to get it pinned correctly and the car started right up! I've never felt so relieved after resolving a car issue...whew!

Thank you to everyone who chimed in to help me troubleshoot this!

[abscate]

Your systematic approach paid off, and led you to the fault.

That’s a tough one.

I’ve found a cheap analog voltmeter is better than the digital type. The digital sample at about 1 Hz, so you can miss intermittent like this. You will see it on an analog meter nicely

[jonesg]

It seemed to me the fuse getting no power pointed to something physical rather than software glitch.

...back to modifying my cupholder...