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1967 mustang coupe v8 289
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Discussion Starter · #1 ·
weird question.. the brown wire (262 on diagram) that plugs into the starter solenoid.. i had this unplugged to bypass the resister wire for my pertronix ignition. would this have any affect on how my gauges work? or not work? or is that completely different? i saw in a youtube video of a guy bench testing a gauge cluster and he mentions to check this wire if gauges don't work correctly. which mine haven't been. so i'm wondering if i need this wire plugged in for my gauges to get correct power to work.
 

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I'm pretty sure that the brown wire is only connected to the ignition coil to bypass the pink wire and give it 12v while you're starting the car. It shouldn't have anything to do with the gauges.

Do any of your gauges work? How about the wipers, clock, and turn signal indicators?

The Amp gauge is on it's own and ought to twitch if you turn the headlights on. The Fuel, Temp, and Oil gauges are all run off the voltage regulator. If it's those three that aren't working you probably need to check the power and ground to the regulator and make sure it's still good.
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Discussion Starter · #3 ·
I'm pretty sure that the brown wire is only connected to the ignition coil to bypass the pink wire and give it 12v while you're starting the car. It shouldn't have anything to do with the gauges.

Do any of your gauges work? How about the wipers, clock, and turn signal indicators?

The Amp gauge is on it's own and ought to twitch if you turn the headlights on. The Fuel, Temp, and Oil gauges are all run off the voltage regulator. If it's those three that aren't working you probably need to check the power and ground to the regulator and make sure it's still good.
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ok thanks. thats what i thought. not sure why the guy in the video thought that wire has anything to do with it. i've been fighting my oil/temp/gas gauge for years. they all just go to H instantly. i have tried new senders, gauges and regulators. with the same results. only difference is the temp gauge goes to H very slowly with the engine off. i'll continue trouble shooting. it's grounding out somewhere and its driving me nuts.
 

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Check and possibly replace the instrument panel voltage regulator. It takes the 12v and knocks it down to 5v for operating the gauges, and it pulses, so measuring that with a digital ohmeter is kind of difficult. Use an analog (needle sweep) type.
 

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Discussion Starter · #5 ·
Check and possibly replace the instrument panel voltage regulator. It takes the 12v and knocks it down to 5v for operating the gauges, and it pulses, so measuring that with a digital ohmeter is kind of difficult. Use an analog (needle sweep) type.
i have tried 4 different ivr's. 2 different solid state ones from npd and 2 different mechanical ones. same results. they all put out the 5v but for some reason the gauges want to swing all the way up as soon as i turn the key. i've checked and rechecked the cluster wiring. it all seems good. same result with the cluster inside and out of the dash. so its not touching any metal inside.
 

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If they all go to hot that sounds like they're grounding out. Do you have the little cardboard strips on the back to isolate the gauge posts from the cluster housing?
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i have tried 4 different ivr's. 2 different solid state ones from npd and 2 different mechanical ones. same results. they all put out the 5v but for some reason the gauges want to swing all the way up as soon as i turn the key. i've checked and rechecked the cluster wiring. it all seems good. same result with the cluster inside and out of the dash. so its not touching any metal inside.
Your IVR isn't grounded. There should be a ground wire from the IVR mounting screw to the metal portion of the dash.
 

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Discussion Starter · #9 ·
Your IVR isn't grounded. There should be a ground wire from the IVR mounting screw to the metal portion of the dash.
there is? the only ground i see is that black butt connector that plugs into the peice that screws between the ivr and cluster
 

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Discussion Starter · #10 ·
wire 57 in the diagram if thats what you are referring to. that is present
 

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Do the gauges go high with the wire to the sender disconnected from the sender?
 

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there is? the only ground i see is that black butt connector that plugs into the peice that screws between the ivr and cluster
Is it connected to ground? Use an ohmmeter between the metal portion of the cluster and the metal portion of the dash... you should have no more than 0.1 ohm resistance.
 

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Discussion Starter · #14 ·
Is it connected to ground? Use an ohmmeter between the metal portion of the cluster and the metal portion of the dash... you should have no more than 0.1 ohm resistance.
that wire goes to the connector.
 

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Discussion Starter · #15 ·
i think i found my problem. that wire wasn't grounding good enough. it had some excess rubber from the boot. cut some of it off and it seems to be working now. thanks yous guys
 
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