Speedometer not working
#1
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I recently purchased an 83 euro and the sales description claims:
Since the PO has basically vanished I am on my own trying to figure this one out. Any suggestions on the steps to fix a non-functioning speedometer that supposedly needed and now has a new sending unit ?
speedometer sending unit replaced
#2
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Isn't the sending unit located on the transaxle somewhere? Caveot Emptor on Ebay I'm afraid.
#3
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As Brad said, the sending unit is mounted in the differential cover on the transaxle. Not sure about the Euro cars, but on the US cars the transmission wiring is routed through the spare tire well under a cover at the front of the well. I would check the connections there first.
Mike
Mike
#5
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The gear drives the odometer. The sender is mounted on the back outside of the diff cover and senses magnets on a aluminum wheel on the diff. It sends pulses to the speedometer (which works just like a tachometer) .When you rotate the rear wheels the switch opens and closes about 9 times per revolution. Check with your multi meter.
#6
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Your problem most likely resides in the printed circuit board to speedo. There is a board which is rivited to the printed circuit and these rivets dont always work great. They tend to corrode and then not pass electricity.
#7
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or finally the speedo is just broken and needs rebuilt...
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#8
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trying to ovoid pulling the pod, i'm alttile green on that adventure...so will check the sending unit end that plugs into the back of the diff. it should be new but regardless, what am looking for once it is disconnected ?
#9
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Pulling the dash is easy (after you do it 50x!!!
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On the back of the cluster is the circuit panel. Clean everything with an eraser, look for broken circuits, etc.
Finally, remove speedo and send to a shop in california, can't remember the name, do a search, they do great work. $200. Done.
Brad
#10
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yesterday i checked the wiring in the spare tire area, it was very clean but gave it a spray. today was under the car and i think i found the sending unit, it looks intact.
from what others describe the sending unit sends a pulse from magnets, can this be tested with a meter at the spare tire area ?????
trying to avoid pulling the pod, or does it look like that is next >
thanks
from what others describe the sending unit sends a pulse from magnets, can this be tested with a meter at the spare tire area ?????
trying to avoid pulling the pod, or does it look like that is next >
thanks
#13
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Yep, Dwane has a good writeup on how to fix the speedo. It is not hard work just tedious. I have done it 3 or 4 times now so it is getting pretty simple. If you do a re-solder on the printed circuit board, check continuity between the open rivits and the prongs that go inside the speedo unit. If you have it on all 4 of them, I will bet you will have no further issues with the speedo. Just make sure you don't get the board too hot while soldring. The odometer does run on what was some kind of nylon type gear that just crumbles in your hand. The gear that Rennbay uses is much better and should last the life of the car. It is easy as pie to change.
Good luck, let me know if you run into issues. I will be glad to talk with you about it if you need it.
Cheers,
Good luck, let me know if you run into issues. I will be glad to talk with you about it if you need it.
Cheers,
#14
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Jack up one rear wheel, put a meter (in ohms)across the two wires in connector in front of spare wheel, turn the lifted wheel- should go open/closed/open/closed . Very unlikely the sender has failed, its just a reed relay triggered by magnets. next is to check you see the same open/close cycle at the central panel - forget the plug code now - there will be a post by WallyP somewhere listing it. If its reaching there, next is the pod, and if you follow Dwayne's process its not too bad - did it myself recently. Before the actual speedo or its printed circuit, it just could be bad contact at one of the connectors onto the pod - the fingers in the connectors are soft and bend easily, and you might also have some corrosion in there on the copper tracks. These clean up with an eraser generally. Check for other oddities on the instruments - mine showed a flick up in temp gauge when lights went on - poor ground contacts for lighting caused this, cleaning and retensioning contacts fixed it.
jp 83 Euro S AT 54k
jp 83 Euro S AT 54k
#15
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No one does a better job of showing the step-by-step of a job than Dwayne: http://dwaynesgarage.norcal928.org/