Unusual gauge readings after cluster R & R
12-01-2008 | 03:53 PM
#1
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From: Northern NJ
Unusual gauge readings after cluster R & R
Just replaced my odometer gear, foiled the instrument cluster light lenses, replaced bulbs with #158 bulbs (3.3W), and polished the cluster lens (cover) with Novus Plastic Polish. All of that works/looks great. Also cleaned the contacts on the printed circuit board (where the harness connectors attach) with a rubber eraser and then some contact cleaner, as well as spraying some contact cleaner on the harness connectors. Let it all dry and reassenbled. Everything seemd great.
A couple weeks later, after sitting for a while, the gauges seem to read differently than they had. Temp gauge reads higher (after warm up), gas gauge reads lower, oil pressure gauge reads higher (after warm up), volt gauge reads higher. All of these readings are off a bit (not a lot, but enough to make me wonder if there's a problem). Battery charge checks out fine, but I put it on the charger for a bit to make sure it's fully charged. No change on the gauge readings.
Could a bad connection to the instrument cluster cause these readings? Specifically, could a bad connection cause higher temp gauge reading, lower gas gauge reading, higher oil pressure reading, and higher volt gauge reading? I would assume that a bad connection would cause lower voltage or higher resistance in the circuits to the gauges.
What, exactly, does the volt gauge measure? With a fully charged battery, the gauge used to read about 12.5 - 13.0 volts (at idle). Now, it's almost 14.0, and stays there even after a long drive. Is this normal (and now correct after cleaning the contacts)? Where/how can I use a voltmeter to confirm the gauge reading? Across the battery terminals while running? Where's the best place to check in order to most accurately reflect the gauge reading?
As far as the oil pressure reading --
I recently switched to Redline 15W50 (from Syntec 5W50), and this is the first time it's been relatively cold outside since the switch. Possibly, the new reading is also correct. It's just that the gauge stays pegged at max for longer than before, then doesn't come down as far after the engine is warm.
In the end, I think that confirming the volt gauge reading might be indicative of a problem, or not.
A couple weeks later, after sitting for a while, the gauges seem to read differently than they had. Temp gauge reads higher (after warm up), gas gauge reads lower, oil pressure gauge reads higher (after warm up), volt gauge reads higher. All of these readings are off a bit (not a lot, but enough to make me wonder if there's a problem). Battery charge checks out fine, but I put it on the charger for a bit to make sure it's fully charged. No change on the gauge readings.
Could a bad connection to the instrument cluster cause these readings? Specifically, could a bad connection cause higher temp gauge reading, lower gas gauge reading, higher oil pressure reading, and higher volt gauge reading? I would assume that a bad connection would cause lower voltage or higher resistance in the circuits to the gauges.
What, exactly, does the volt gauge measure? With a fully charged battery, the gauge used to read about 12.5 - 13.0 volts (at idle). Now, it's almost 14.0, and stays there even after a long drive. Is this normal (and now correct after cleaning the contacts)? Where/how can I use a voltmeter to confirm the gauge reading? Across the battery terminals while running? Where's the best place to check in order to most accurately reflect the gauge reading?
As far as the oil pressure reading --
I recently switched to Redline 15W50 (from Syntec 5W50), and this is the first time it's been relatively cold outside since the switch. Possibly, the new reading is also correct. It's just that the gauge stays pegged at max for longer than before, then doesn't come down as far after the engine is warm.
In the end, I think that confirming the volt gauge reading might be indicative of a problem, or not.
12-01-2008 | 04:03 PM
#2
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From: Rosaria, Cascadia
Good voltmeter at the battery with the car running should find you somewhere in the 13-14 range...that's how I'd check your battery reading.
From what I've heard (I had an early so I didn't have a voltmeter in the car), the gauge isn't very accurate.
From what I've heard (I had an early so I didn't have a voltmeter in the car), the gauge isn't very accurate.