After removing the cluster to do a Dave Barton 25 tooth repair on the odometer, I've reinstalled the cluster with the following problem:

What works: Turn signal lights, ignition lights, clock.

What doesn't: Speedometer, Odometer, Fuel, Oil Pressure gauges, change-up indicator and anything else that uses fuse #16.

Fuse #16 was OK, still I cleaned the terminals and put a new fuse in anyway. Still no good. Not sure where to go next. Maybe a ground, or the Instrument Voltage regulator?

Any help will be welcome.

 

instrument stabilizer or regulator.....google it an you will find a guy who bought a regulator for 49 cents...and shipping was 5 dollars....!!! or local junk yard....

never mind here it is...
K-Jet.org | Instrument Cluster Voltage Regulators

 

Do any of the idiot lights (oil, battery, service, etc) come on when the key is turned to the II position? If not, then it sounds like the fuse that brings power to the cluster might not be installed or installed properly. This fuse looks like a little flexible plastic circuit board and is installed across two screws on the top of the speedo. If this is blown or not installed, pretty much nothing on the cluster will work.

 

As you suggested, I picked up a junkyard instrument voltage regulator and swapped it out. Still no good. Nothing on fuse circuits 15 or 16 works, including (#16) right parking lights, instruments, change-up light, panel lights and (#15) left parking lights and license plate lights. Fuses are good. I'm baffled. Any ideas?

 

act1292 - idiot lights non-op! Didn't know that plastic thingy was a fuse. I don't see any discontinuity in the copper, but it has separated from the plastic where the copper gets thinner. Ohmmeter shows continuity. Also, I checked voltage to the main fuse box and it checks out OK.

 

Well, if you have continuity from the two posts that the plastic circuit thingy, then it's time to chase power back further. Power comes into the cluster through the speedo circuit board (red wire I believe). The power then comes down to the cluster circuit board through the bare metal U-shaped wire (kinda looks like a staple). If you follow the traces, you'll see it then travels through the plastic circuit fuse. Check to see if you have 12 volts along this path.

 

I'm having the exact same problem after performing the odometer repair. Initially after I connected everything back, only the speedometer is not working, I then try to wiggle the wires hoping to get it work, after that nothing is working anymore! The only things that work now are instrument lights, indicators, high beam warning light and main beam light. When the key is in "on" position, the idiot lights does not light up. I've purchase a few 7180 regulator and replaced, still don't work. Fuse 16 is ok.

 

Did you try tracing the power as described in my previous posts on this thread?

 

I haven't acquired a multimeter yet. But presuming that there is no power, what can I do? The fuse is ok.

 

if there's no power, you go backwards, checking each connection towards the power source til you find power, and figure out why its not getting to where its supposed to.

 

I read from the forum that the power for the instrument comes from the 3 pin plug, since the instrument cluster illumination lights are ok, I assumed there is power going in. Where is the ground for the instrument cluster?

 

One side note, before this my car was heaving alternator problem, but that happened after the instrument problem. I replaced the brushes and regulator for the alternator. After the alternator service, the battery charging light will remain "on" on the instrument. The mechanic install an external charging light which will work as usual.

 

Is the alternator charging at all? Test that first, the repair sounds a little dodgy... I don't like that "external charging light"--these kinds of rigamaroles lead to badly behaving Volvos!

 

Since the alternator fix the car no longer cut off half way. The external charging light is a temporary solution since the electrician cannot figure out the instrument problem. Since the original charging stays on, he use an external one to make sure it charges normally. Surprisingly the external light is ok, it will off after the car is started.

 

Illumination lights get their power through a source separate from the speedometer and idiot lights. As my post stated earlier in this thread, power for the speedo comes in through the 3 pin edge connector, etc. A multimeter isn't necessary for this kind of tracing. A 12v light bulb with two leads will suffice.

 

the late 240's instrument panel has two grounds. one is pin 2 of the 3 pin speedo connector, but AFAIK, thats only for the speedo. the other is pin 4 of connector '32', which is the 6 pin 'smile' shaped connector... pin 4 is on one end of this connector and is a black wire, which goes to the main interior ground on the left side of the transmission hump between the shifter and the lower center console.

the dashboard illumination (not indicator) lights get their power via the dimmer rheostat on connector 31 pin 10 (brown wire). 31 is the full circular connector. said lights are grounded via 32/4 same as most of the rest of the panel.

pin 31/9 (white wire) is always-on power, for the clock. this comes from fuse 8.

the main power to the instrument panel is the blue wire on pin 3 of the 3-pin edge connector that goes to the speedo, and this power comes from pin 15R of the ignition key, it is 'on' in positions II (run) and III (start).

 

Pierce, just for a confirmation, the main power for the instrument comes from this blue wire?

http://2.bp.blogspot.com/_kB6F71TLY0...0/ABCD0014.JPG

 

yup. that blue wire should be powered when the ignition is in position II, its connected to ignition switch pin 15R

when its plugged into the speedometer, that blue power wire should be on TOP, the wires come in from the side away from the speedo and clock or tach.

odd, my 1990 and 1992 wiring diagrams says the third wire should be green/white, and it looks red/black or something in your picture

oh crap. my 1989 diagram shows the POWER wire is red/black, and the speedo signal wire is blue. the power wire is on top, pin 3, the black ground wire is in the middle, pin 2, and the speedo signal wire is on the bottom, pin 1

so... try the red/black wire for power

 

Thanks!, anyway, what is the yellow wire with a single connector that plug to the bottom right (from the driver's view) near to the fuel/temp gauge?

 

thats the OD light on a automatic (and upshift light on a manual). my diagrams say that wire is yellow/red on an 1989 or 1990.