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Discussion Starter #1
I'm having a problem with all of my gauges the oil gauge (after market) looks like it works as far as i know but the gas jumps to over full every time it gets power the alternator charge gauge ive never seen move so i'm assuming its not working either ive used a test light on the wires for the gas and temp and they give a solid light it doesn't pulse is it my instrument voltage regulator? Any help would be appreciated!
 

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Is that connector at firewall being jumped a 4 pin connector? Is your car now a manual shift?
As said above for manual cars, there was a factory "jumper loop" there. Neutral safety bypass. No jumper for car with automatics.

I'm gonna guess your backup lights do not work as looks like no wire harness present for them.
 

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I'm going to guess that the aftermarket oil pressure gauge uses 12 V to work and that whomever installed it applied 12V to the gauge power feed for the cluster. The factory gauges require a 5V supply, which would explain why your fuel gauge pegs when power is applied. The charge gauge is separate from the oil, temp and fuel gauges and works differently.
 

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Discussion Starter #6 (Edited)
Is that connector at firewall being jumped a 4 pin connector? Is your car now a manual shift?
As said above for manual cars, there was a factory "jumper loop" there. Neutral safety bypass. No jumper for car with automatics.

I'm gonna guess your backup lights do not work as looks like no wire harness present for them.
Yes it is a 4 pin connector but no i have a auto trans and the backup lights do not work. I do have this plug that looks like it would be able to plug into the connector being jumped if only it could reach
 

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Yes it is a 4 pin connector but no i have a auto trans and the backup lights do not work. I do have this plug that looks like it would be able to plug into the connector being jumped if only it could reach
So thinking you have an automatic, and 4 pin conn jumper-ed, safety bypassed, your car would try to start in any gear not just PARK??? If so now you know way
 

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The ammeter doesn't run off the IVR like the other gauges, it is wired in a parallel shunt to the battery and alternator output circuit and typically gets all corroded inside and just quits working. Like the rocketman says, a bad IVR or poorly grounded one can affect your gauges, but it will be the fuel, oil and water temp gauges that will ALL mimic the same behavior. If it's just the fuel gauge it could be a short to ground in the reference-side of the gauge circuit.
 

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Discussion Starter #10 (Edited)
The ammeter doesn't run off the IVR like the other gauges, it is wired in a parallel shunt to the battery and alternator output circuit and typically gets all corroded inside and just quits working. Like the rocketman says, a bad IVR or poorly grounded one can affect your gauges, but it will be the fuel, oil and water temp gauges that will ALL mimic the same behavior. If it's just the fuel gauge it could be a short to ground in the reference-side of the gauge circuit.
It is all my gauges that are dead just not oil pressure its after market this is the one i think https://shop.advanceautoparts.com/p/autometer-100-psi-mechanical-oil-pressure-gauge-4421/17121923-P?searchTerm=autometer Ive tested the ground for the IVR and it seems to be a good ground so i think im just going to swing by npd and pick up a new IVR
 

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You can check the IVR by disconnecting the wire at the sender and reading the voltage on it (one voltmeter lead to the wire that was on the sender, one lead to ground). You should see a pulsing signal that goes between about 3 to 6 volts. You can use the temperature sender or the fuel sender if they are acting the same way - the same voltage source (IVR) feeds both gauges.
 

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Discussion Starter #12 (Edited)
You can check the IVR by disconnecting the wire at the sender and reading the voltage on it (one voltmeter lead to the wire that was on the sender, one lead to ground). You should see a pulsing signal that goes between about 3 to 6 volts. You can use the temperature sender or the fuel sender if they are acting the same way - the same voltage source (IVR) feeds both gauges.
I just tested it it does not pulse it stays at around 10.22v
 

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Then either the cluster is not wired correctly or the IVR is failed. You really should disconnect the gauges until you get this fixed so you don't kill the gauges. You can do that by disconnecting the wires at the senders
 
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