1986 Volvo Speedo quit working.

Since my Astro is still down, waiting for me to pull the intake manifold, I've purchased an '86 Volvo 740 Turbo wagon 2.3L to get me by in the interim.

One of the many things I would like to fix on this car is the speedo. All functions (speedo, odo, trip) are not working. I pulled the instrument cluster to find that there is no mechanical spinning cable attached to the rear of this speedo. It must get an electronic signal from somewhere instead.

Anyone run into this sort of problem in a similar vehicle? Do you have any suggestions on troubleshooting, places to start perhaps?

TIA

Reply to
TomO
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My dive buddy owns a shop that specializes in Volvo repairs and he also has a huge inventory of Volvo used parts. His email address is snipped-for-privacy@comcast.net , send him your question and tell him NHdiver of Bottoms Up Divers gave you his name. He has a huge customer base with mostly older, high mileage Volvo's, I know he has addressed this problem before.

Al Bottoms Up Divers

Reply to
ajtessier

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Don
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Reply to
Don

Thanks Don. A quick browse of their website led me to believe that they can repair it for me but are not terribly interested in providing troubleshooting hints and tips. I guess if all else fails, I could just have someone else fix it for me, but where's the fun in that?

Reply to
TomO

Thanks Al. I may have to do just that. More research has taught me that the speed sensor / signal generator is located in the rear differential on this vehicle. A quick check after work today showed that the wiring appears to be intact at the 'punkin' and I followed it up to the first sonnection point slightly forward of the left rear tail light. At least I now know that I'm chasing a grn/wht - brn pair.

Maybe the VolvoDoctor will know what sort of signal or voltage I should be able to read with either a scope or a meter on the lines. That would be quite helpful in determining if I have a problem at the source or in the speedo itself.

Reply to
TomO

Won't hurt to ask. I am in Austin and have been to his shop (actually his kitchen and adjoining room). I found him extremely knowledgeable, friendly and helpful. You will need to put some kind of meter or scope on the signal lead to verify if the head unit is bad. IT will not be easy to get parts to repair the head unit if that's what you were referring to. First, of course, you will have to verify that the head unit is indeed bad.

Don

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Reply to
Donald Lewis

I used to find the Volvo Haynes manual was a pretty good one for giving all those kind of readings. Their 240 books were right on.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

I'll give the hatnes manual a go then. I was at the FLAPS yesterday, but they did not have the one I needed for this car. I'll be sure and check elsewhere.

Reply to
TomO

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