1998 Ford Mustang Instrument Cluster

1998 FORD MUSTANG
109,000 MILES • 6 CYL • 2WD • MANUAL
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LVI56
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I took my car in for a smog test last week. (california). It failed the functional test due to the MIL and VSS malfunction. Prior to this my speedometer did not work, I had been waiting on getting a job to fix that. I didn't even notice that the check engine like (MIL) would not come on when I start my car.

I got some diagrams and decided to check it out myself. I took our the instrument cluster and verified all the bulbs were good. I took a multimeter and started checking the resistance of the related terminals on the wiring harness. I was getting signal from the VSS, but not from the MIL it seemed. Then my hand slipped, being in a tight spot trying to keep the leads of the multimeter on the terminals of the harness, and there was a small spark. Keep in mind I had the battery connected to do the tests. After connecting everything I tried to start my car and it wouldn't turn over.
When I turn the key I don't hear the click of the fuel pump. I have some lights on the cluster but some are off (such as the battery light). All other guages look good, and I can turn on the lights. I checked all the fuses and they are good.
So what's going on? Did that spark short something? How can I track it down or should I even try?
Aug 23, 2009 at 7:14 PM
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MJR346
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You have two fuse panels, one under the hood and one under the dash, check both of those and let us know
Aug 24, 2009 at 9:15 PM
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LVI56
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Checked fuses, all fuses are good.
Aug 24, 2009 at 9:53 PM
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MJR346
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The mil receives ground from the PCM. It will only come on at bulb checkout and when the PCM commands it if I remember.

The VSS is a a/c voltage signal from the transmission if I remember. it increases as speed increases.

If half the dash isn't working, check the plug ins on the cluster for looseness, and you have the diagrams, I beleive there are 2 powers and a ground at least. Check all of them.

I've had issues in the past with the printed circuit board on back the cluster.

Also is this definitely a 1998 or 1999 Model year vehicle? (I'm asking as the clusters are completely different between 1998 and 1999, with 1999 (roughly August 1998 and later) having a PATS key system tied to the cluster. and will cause no starts etc. if something is amiss.

Please report back what you find.
Aug 25, 2009 at 7:21 PM
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LVI56
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Thanks, It's defiantly a 1998. If the instrument cluster board is dead, or part of it is, that wouldn't cause no-starts? I checked all the connections and they are good.
Something is keeping the fuel pump from coming on, while at the same time causing the instrument cluster to malfunction. If they are not related then that's some damn terrible luck. The PCM makes the most sense from what I see.
Aug 25, 2009 at 7:45 PM
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MJR346
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Actually you have a PCM relay that powers PCM. Known problem sometimes
Aug 25, 2009 at 8:02 PM