Windows Won't Roll Down

[ShadowsPapa]

0.7 K ohms = 700 ohms?

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[ShadowsPapa]

Good, the drugs and infections haven't made me a total space cadet. Basic math still works HA.

Sadly, this is too late, but a classic case for "the forums might have saved some headache" as a number of others have run into this exact same thing - going back at least 4 years. IF it matters any or makes the OP feel any better - he ain't the first to experience this nightmare, and there's usually not a "what one thing can I look at to fix it".
It's something you can't really search for other than "what's the best way to........" sort of question. Others have been there and can help avoid.
Don't be shy about asking a question -you'll get a few "just use the search" - but ignore those and focus on those who link to the stories others have told.
You are almost never the first person to have done or tried something.

For the OP -
Hang in there - Hootbro knows all about this stuff and is among the best sources for troubleshooting this sort of thing. He's seen it several times over the years and knows his shit.

 

[Hootbro]

That is 700 ohms which is high. That tells me you have a broken ground plane within the PDC fuse box and is why the RUN/ACC 1 relay will not latch.

Proper fix is a new PDC. Other options is someone with componet level electronic experience could possible repair the circuit board. Another option is to scab an external relay.

 

[ShadowsPapa]

that's something I could sit at a desk and fix (former Compaq certified warranty repair - doing board level repairs on their laptops as well as other repairs at CCC)
But it would take far too long to get it here and back CA to IA

The other option - salvage yard?

I'd check with Benny on the part - he'll want the VIN - but I bet it isn't cheap.

 

[Hootbro]

I just curious, can you remove the relay and check just the socket side on the PDC for PIN 85 to ground? I am just wanting to see if it is true open (infinity) and not just that 700 ohms which I suspect is back feeding through the relay coil to the BCM power output PIN 86. Either way, still think the PDC ground plane internal is messed up for that leg.

I think when you originally poked through the GN/BU wire on the firewall and the first time you went to ACC or RUN, the BCM sent the 12vdc for the relay turn on and was shorted without a fuse and the circuit board ground plane trace in the PDC was the weak link and is what blew

 

[KAExcaliber]

I just curious, can you remove the relay and check just the socket side on the PDC for PIN 85 to ground? I am just wanting to see if it is true open (infinity) and not just that 700 ohms which I suspect is back feeding through the relay coil to the BCM power output PIN 86. Either way, still think the PDC ground plane internal is messed up for that leg.

You lost me here. Check socket 85 for continuity to ground?

I think when you originally poked through the GN/BU wire on the firewall and the first time you went to ACC or RUN, the BCM sent the 12vdc for the relay turn on and was shorted without a fuse and the circuit board ground plane trace in the PDC was the weak link and is what blew

Makes sense.
Are RUN 1 and RUN/ ACC 1 connected? Maybe they share a common ground on circuit board?

I'll reach out to Benny to see what a new one costs and will probably pull the board at some point to see if there us any visible damage. There are few places nearby that should be able to repair it, if possible. In might just scab in some relays for now.

 

[Hootbro]

You lost me here. Check socket 85 for continuity to ground?

Take the relay RUN/ACC 1 out of the PDC. Where PIN 85 of the removed relay goes into that PDC, stick one meter lead on the socket hole terminal of the PDC and the other meter lead on a ground point like on the fender or even the battery negative side terminal. With the meter on ohms scale, what does it read?

 

[KAExcaliber]

Take the relay RUN/ACC 1 out of the PDC. Where PIN 85 of the removed relay goes into that PDC, stick one meter lead on the socket hole terminal of the PDC and the other meter lead on a ground point like on the fender or even the battery negative side terminal. With the meter on ohms scale, what does it read?

 

[ShadowsPapa]

895 ohms

 

[KAExcaliber]

I scabbed up the Run/ Acc relay with pin 85 connected to an external ground and the respective accessories seem to work just fine. So I think you were spot on as far as blowing the PDC ground on the Run 1 and Run/ Acc 1 relay leg.

Sent Benny a message and now just waiting to hear back on a new PDC. Still need to call a few circuit board shops to see if what it would cost/ and if it’s repairable. Not sure that’s something I would try to tackle myself.

 

[ShadowsPapa]

I scabbed up the Run/ Acc relay with pin 85 connected to an external ground and the respective accessories seem to work just fine. So I think you were spot on as far as blowing the PDC ground on the Run 1 and Run/ Acc 1 relay leg.

Sent Benny a message and now just waiting to hear back on a new PDC. Still need to call a few circuit board shops to see if what it would cost/ and if it’s repairable. Not sure that’s something I would try to tackle myself.

If you buy a new one, send me the old (I'll pay shipping) and I'll see about fixing it.

 

[Hootbro]

Yeah, that is effectively a high resistance open.

Thanks for entertaining me. Sounds like you got a handle on what you need to do.

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