Hello!

I have a 1986 Volvo 240. The odometer was not working so I bought a new little odometer gear and replaced it. The old gear had 2 broken teeth. That is the easy part. Unfortunately, I didn't make a wiring diagram of the wires that plug into the cluster. I plugged the circular harness in, the half circle harness in, no problem. There's a yellow/red wire I plugged into a male terminal on the lower right as you are looking at the cluster while sitting in the drivers seat. There's a white/red wire I tried to plug into a double male terminal just to the right of the speedometer. Also a plug with 3 wires doesn't seem to have a place to plug into in the cluster. To compound my problems, I evidently unscrewed 2 little pieces of cellephane that have a copper wire through them. The cellophane strips are about 2 1/2 " in length and 1/4" in width and have 2 screw holes in them. I don't know where they go. Is this cluster "kaput" and should I try to find another instrument cluster for this year? Or is there some hope that I can get this back together and working? Any advice would be welcome.
Thanks, Pleasant Hill Bill

You just "might" be the luckiest installer of an instrument cluster, I did say "might". The double male spade lugs to the right of the speedo should have NO wires attached to them unless you want to "fry" the speedo electronics, don't ask me how I know! The beauty is that you didn't have the three wire edge connector plugged into the back of the speedo... so you just "might" be okay!

The plastic flex circuit you mention runs between the two bolts above the speedo assembly, it needs to be installed for everything to work properly.

jorrell
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92 245 287K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

Is it possible to short out the odometer sending unit or another fuse somewhere? I made the mistake mentioned above and connected a tach wire to the double male connector next to the speedo. I have swapped clusters and gauges and I'm still getting nothing. The tach, speedo, and temp gauges all work.

Also my gas gauge isn't working either, so right now I have no concept of how far I've gone or how much gas I have left.

This thread saved me some substantial grief tonight. I was about to hook up the tach wire to the double male connector when I figured I had better first look and see what I could find here about that decision.

Thanks for sharing.

Craig

Just think...it is a three year old thread and we have had at least 6 or 7 posts a year where someone asks what the red and white wire is for...or fails to ask.

Take the precaution for the next person in there, either snip off the connector or at least label it with a skull and crossbones.

I'm glad you got yours going again - you're very fortunate to have left the speedo connector detached, and also the clear-plastic fuse strip that goes across the top of the speedo. I think those two omissions saved you from frying your cluster.

jorrell has helped me out of more electrical tough spots than I can recall, and I bow deeply to his education and experience.
I have a couple additional tidbits re. the double spade connector.

The double spade connector is for the cruise control, for those cars that have one. If I recall correctly, a solid orange wire goes to that terminal (use either of the twin blades).

The hazard in the system is the red+white wire. It carries high voltage 'pops' from the ignition coil and drives the tachometer on cars which have one. Plugging the red+white wire into anything else tends to fry the cluster. Been there done that! The appearance of smoke from your dash area is a very scary thing.
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Sven: '89 245 NA, 951 ECU, expanded air dam, forward belly pan reaches oem belly pan, airbox heater upgraded, E-fan, 205/65-15 at 50 psi, IPD sways, no a/c-p/s belt, E-Codes, amber front corner reflectors, aero front face, quad horns, tach, small clock.

The other terminal on the double spade lug is for the upshift indicator for manual transmission equipped cars. Blue wire, I think.

And the yellow/red wire that attaches to the lower right side is for the overdrive indicator light.

So:

1. Didn't connect the white/red wire to anything.

2. Connected the yellow/red wire to the male connector on the right.

3. Connected the edge connector.

4. Test drove it.

It all works! Speedometer, fuel gauge, temp gauge, and best of all, the odometer and trip meter both work just fine!

Thanks to everyone!

Pleasant Hill Bill

Question-
Does anybody know what those 2 connectors (that you're not supposed to connect anything to) are actually for, or what they do (other than fry speedos of course...)
Just curious.

God Bless
Koos

Yes, they are used to "calibrate" the speedo magnet during production BEFORE the electronics are attached. In later 240 models Volvo installed a rubber ring over those two male terminals in order to discourage accidental connections in the field.
jorrell
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92 245 287K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

So: 1. Connect the cellophane connectors (2 of them) between the two screws that are on either side of the top of the speedo?

2. Connect the "edge connector" to the little plate connected to the speedo that is sticking out of the rear left side of back of the speedo?

Thanks!

Bill

Red/white is the tachometer wire, it will fry your speedo.