RRS issues after reassembly

pinkytoe69

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Jan 14, 2012
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To recap: bought an L320 with non-airbag front end collision damage. No codes prior to disassembly.

I got the front end back on and the radiator filled & bled.

Everything starts out ok, but the ride height then gives a failure along with stability control, HDC and special functions..

Pops a transmission fault when I put in gear, but it goes back and forth fine (just driveway testing so far).

Code reader says they are all communication issues (I can get the actual codes tonight).

Did I miss a ground or connector?
 

discostew

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Sep 14, 2010
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Get the codes out of it. Since it happens when you put it in gear I would suspect the park indicator fault kind of a deal. But untill we know a code # it's just a guess. The codes I'm thinking it might be usually end up being a wire or the shifter assembly.
 

pinkytoe69

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Jan 14, 2012
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minnesota
Get the codes out of it.

Voltage at the battery at idle is 13.97.

Also, as mentioned in a different thread, I couldn't get the key out after the tow dropped it off and I backed it into the garage.

That hasn't been an issue since reassembly and testing.

564395644056441564425644356444
 
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discostew

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Sep 14, 2010
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Just like I thought with the park input deal. I just dealt with that but I have to go back and look at where my guy found the open wire.
The code that says invalid data just means that the air suspension system has a fault in it. All data from modules with codes stored is deemed invalid.
You need a compressor most likely for the pressure slow to rise code. I have a brand new old design compressor I can sell you cheap. But the new AMK brand compressors have been pretty bullet proof.
The no coms to the tire pressure monitor might be unplugged or just deadheaded. It's above the overhead console ( front dome lamp )
 

pinkytoe69

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Jan 14, 2012
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Just like I thought with the park input deal. I just dealt with that but I have to go back and look at where my guy found the open wire.

Cool, thanks! Is this the passenger side foot rail stuff?

The code that says invalid data just means that the air suspension system has a fault in it. All data from modules with codes stored is deemed invalid.
You need a compressor most likely for the pressure slow to rise code. I have a brand new old design compressor I can sell you cheap. But the new AMK brand compressors have been pretty bullet proof.
The no coms to the tire pressure monitor might be unplugged or just deadheaded. It's above the overhead console ( front dome lamp )

I drove this thing around the sellers house before buying and none of this happened. How did all this shit pop just from basically doing a glorified condenser and radiator job?
 

pinkytoe69

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Jan 14, 2012
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minnesota
I doubt this matters, but the fog light wiring got chopped and the front left parking sensor is cut off.

Other than me disconnecting the remaining fog, it's just like it was before I started (assuming I got all the connections back).
 

discostew

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Sep 14, 2010
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I'm thinking it was more near the B pillar on the right side. I'll get with my friend and get a better description of where he found the break. The park input signal should change state when not in park. The car compares that signal to what it gets from the trans. Not a difficult circuit to run down.
If you have the schematic look in the trans controls and find that park input signal. First we check that the wire changes state when we move the shifter out of park. Then we see that it's changing state at the other end. Then once we know we have it isolated we can do some voltage drop tests across the whole park input wire.
Wires are cheap to fix. Just gotta find it.
 
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discostew

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I looked into this a little. The code description is park lock signal circuit. The park lock signal comes out of the shifter connector on terminal 2 ( green wire) goes thru 3 connectors on its way to terminal 7 of the trans connector.
My friend said the break in the wire was near the B Pillar area coming off the cross car harness that runs behind the front seats.
The park brake fault was probably low battery voltage. Forgot that one last night
 

pinkytoe69

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Jan 14, 2012
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minnesota
I looked into this a little. The code description is park lock signal circuit. The park lock signal comes out of the shifter connector on terminal 2 ( green wire) goes thru 3 connectors on its way to terminal 7 of the trans connector.
My friend said the break in the wire was near the B Pillar area coming off the cross car harness that runs behind the front seats.

Yikes.

What's involved in getting to that cross harness?
 

discostew

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Yikes.

What's involved in getting to that cross harness?
First you need to check the wire at connectors you can access. Easy shit first. I would first access the shifter connector and inspect it for green fur and what have you. That thing catches any liquid that gets spilled near the console. Then check at the next connector and the next till you get to a place that seems like it's not doing what it is near the shifter.
Also another thing to check is at the shifter connector there's battery positive on terminals 3, 8, and 7. I've seen loss of power on any one of those cause strange shit. I think the way it works is the signal on the park lock circuit gets held at ground when in park. Then it should go up to either 5 volts or maybe battery voltage when in any other range. But I'm going by memory, and I can't remember shit.
 

pinkytoe69

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Jan 14, 2012
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minnesota
First you need to check the wire at connectors you can access. Easy shit first. I would first access the shifter connector and inspect it for green fur and what have you. That thing catches any liquid that gets spilled near the console. Then check at the next connector and the next till you get to a place that seems like it's not doing what it is near the shifter.

Ok Im in. Theres a bunch of dried up coffee in here, but no corrosion on any of the connections that I can see.

Am I moving the shifter in and out of park and checking for changes continuity or amperage on the green wire against a ground?
 

pinkytoe69

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Jan 14, 2012
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Ok the green wire has continuity from the shifter plug to the big whiteish one.

The shifter itself shows the correct position both on the dash and on the code reader live data, so I assume that's working fine.

Don't know if this matters, but the transmission fault only pops when you put it in D

I'm guessing I need to pull some interior and get to the rest of that green wire?
 

discostew

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What happens on that green wire? I'm thinking it's either got voltage when not in park. Even if it's 5 volts or 500mv. That wire should change state in some way when you select anything but park.
Do You have a schematic?
 

pinkytoe69

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Jan 14, 2012
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minnesota
What happens on that green wire? I'm thinking it's either got voltage when not in park. Even if it's 5 volts or 500mv. That wire should change state in some way when you select anything but park.

I'll do some powered-up testing and report back.

I was also gonna test continuity on the wire from the shifter plug to the transmission ecu if that's accessible?

Do You have a schematic?

Attached what I have...
 

Attachments

  • LR3_Engine_and_Transmission_Wiring_Diagrams_pages_24_to_43.pdf
    984.6 KB · Views: 3

discostew

Well-known member
Sep 14, 2010
7,706
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Northern Illinois
So if
Ok the green wire has continuity from the shifter plug to the big whiteish one.

The shifter itself shows the correct position both on the dash and on the code reader live data, so I assume that's working fine.

Don't know if this matters, but the transmission fault only pops when you put it in D

I'm guessing I need to pull some interior and get to the rest of that green wire?
the wire is good out to that white connector then backprobe it there. It could be one of those battery feeds. The shifter can't put any voltage on it if it's not getting it on one of those feeds.
 

pinkytoe69

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Jan 14, 2012
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minnesota
Also another thing to check is at the shifter connector there's battery positive on terminals 3, 8, and 7.

Been PMing with discostew about this. After some multimeter troubleshooting, I went into the rail in search of Green/Pink wire #7.

This is not a good splice...

56488

Hopefully this fixes the transmission fault.
 

discostew

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Sep 14, 2010
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Northern Illinois
Good deal. While your in there there's about 3 or 4 splices you should look at. Look for the green fur and pull on the wires. A shitty splice will just pull apart.
Grey and black splice causes get windows to quit. Green and white makes your remote locks inop. There's a red one in there that causes brake se corrolation faults. and a white and red for seats.
It's kind of fun huh?
 

pinkytoe69

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Jan 14, 2012
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minnesota
Transmission fault is fixed (y)

The other splices seemed fine, and my soldering iron wasn't getting good flow anyway, so I left them.
 

pinkytoe69

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Jan 14, 2012
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181
minnesota
Replaced the air compressor (kudos again to discostew) and slow pressure issue is gone.

Only thing left is the TPMS.