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2008 S80 AWD Automatic 3.2 T6-No revers lights

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dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Re: 2008 S80 AWD Automatic 3.2 T6-No revers lights

Post by dnas501 »

I will tear the dash apart and pull the CEM. Check the connections. The fuses are definitely good.
You have no idea how much I appreciate your input and advice.

jimmy57
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Post by jimmy57 »

You can get the CEM out w/o glovebox removal but it is easier with glovebox removed.

dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

Well. I got the CEM out , pulled apart and looked at the circuits. Visibly relays look like they are OK. There seems to be no easy way to power them up to check if the coils or contacts are bad. All looks good. Nothing burned or discolored. I have power to fuses 11,12,13,14 when the car is running. Not in the off position. Seems normal. To be honest everything looks like its in good shape. I can't figure out which harness I should be checking . Brown,blue etc. The wiring is really well taped and tucked in channels.
Honestly don't know which wire to follow. 62,73 are not numbers. So how do I tell.
Believe it or not I'm usually pretty good at this sort of thing. But this has me baffled.
I'm almost ready to throw in the towel. Any help would be appreciated very much.
Dave

dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

If I could call you I would. That is if you have a few minutes to spare.
Not sure how to get you my phone number. Without putting it on the public post.

jimmy57
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Post by jimmy57 »

The bottom connector on the right side as mounted in car is the C2 connector.
https://qclt.com/html/volvo_ewd_us_eng/ ... 15202.html is link to a 2008 S80 wiring diagram.
go don left side to "component illustrations" then to 4/33-4/56C3. 4/56 IS CEM and you re looking for C2 connector. The map of connector pins is there. Down in the CEM connector are tiny numbers by end terminals in each row. You have to count to find the specific one. The grounding pin for relay coil for K3 is not in the connector as the CEM circuits are direct on board.
I can't help on which relay is it. I have replaced relays on many modules or junction boxes on several makes but not yet on a P3 CEM. The relays that fail do not always show any external signs of a failure.

dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

I'll try and follow that. I should mention that a few months ago. I did remove the cm and wiring. Because I had to replace the fan in the AC system. It's possible the lights haven't worked since then. But just

dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

Finally it all makes sense. I found the wires and checked for power in "car running and in reverse" but no power at 62 or 73. Looks like CEM relay is faulty.
Not sure where this can be repaired. But I'll try and figure out which relay K3 is.
Thank you very much for all your advice.
Without your assistance I'd still be looking for the wires. I would have had to pull the seems and carpets eat to follow them.
I ended up installing a small magnet and proximity switch at the shifter to backfeed the wires.
This should at least pass the inspection and I'll have to see if it's worth further repairs.

dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

Just wanted to say THANK YOU for your assistance.
I'm now going to research a repair service for the CEM.

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RickHaleParker
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Post by RickHaleParker »

dnas501 wrote: 25 Feb 2019, 07:39 I'm now going to research a repair service for the CEM.
They cost ~$30.00 at a Pick-n-Pull.
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1998 C70, B5234T3, 16T, AW50-42, Bosch Motronic 4.4, Special Edition package.
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2004 S60R, B8444S TF80 AWD. Yamaha V8 conversion
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dnas501
Posts: 15
Joined: 21 February 2019
Year and Model: 2008
Location: new york

Post by dnas501 »

Would it need to be programmed?
And would the vehicle run at all with a used unit?

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