Hi all,

Last week my odometer stopped working. I went to the P&P and got a good used odometer cog. Opened up the instrument panel and noticed a burnt electrical smell coming from the area. I replaced the odometer cog with the good one but the odometer is still not working. I was hoping one of you had some tips on what might of gotten fried. I inspected the speedometer/odometer instrument, but nothing seems fried. Thanks for any help you can lend.
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'88 245,M47,Virgos,235K+

The other thing you can do is go back to the pick and pull and get a whole speedometer. For an 88 you have lots of choice. 86 to 91 cars should all have compatable speedometers.

If you are worried about the correct mileage, it is pretty easy to reset on the replacement. Too easy! it makes you worry about buying used cars.

I just went through this with my 93. I am still not 100% sure what was wrong. It tried whole clusters, 3 different speedometers, checked and cleaned all the connections, resoldered the electrical boards, and swapped stepper motors. None of these things worked.

What finally worked was replacing the speedometer IC on the speedometer board. In my case the speedometer always worked. The odometer never worked, and on one of my speedometers the "taximeter" (cruise control output) also did not work.

From my experience: If your speedometer works, and the gears are fine, it is either the stepper motor or the speedometer IC.
First make sure all the solder joints are good.
Check the stepper motor windings.
If these check out suspect the IC

The small odometer gear was missing a tooth. So I figured it was an easy fix.

My speedometer works fine, my cruise control works unreliability and the odometer not at all.
Can you point me in the direction of what exactly the speedometer ic is? I'm not finding it in my bently...
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'88 245,M47,Virgos,235K+

Usually the IC is only damaged when someone connects the tachometer (ignition coil) lead to the cruise/ecu/shift indicator output tab by accident. People say "it smoked" but I don't know what actually cooked, because damage that extensive would not be confined to the odometer and "taximeter" takeoff; it would kill the speedo too.

Take a whiff at the board itself to be sure the electrical smell is new, and coming from the speedometer. Scroll down to the end of this page for some notes on the internals.

I think there might be two major contributors to odometer gear replacement failures: (1) a piece of the old gear remains in the works and (2) the motor and board gets reassembled without the gear fully seated, putting pressure on the motor's connection pins, cracking the solder at the board or winding. I am down to my last PnP gear - most aren't any better than the broken ones, so next time I will need to cough up the $25.
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Art Benstein near Baltimore

If you think nobody cares if you're alive, try missing a couple of car payments.

Its the chip on the speedometers electronic board. It is beside the stepper motor. I am not saying that's your problem. It would be the last thing I would suspect. But they can fail.