I hate beating this dead horse but...am I to understand that the jumper between the fuel and temp is to get the power over from the fuel to the temp gauge? And if this is the case,...if the fuel gauge is bad, will it send power to the temp gauge? In otherwords,..if the fuel gauge goes bad, does the temp gauge then also fail to read? Allen
83 CJ7
I don't think so Bill. There is a regulaor of sorts inside the cluster that regulates the 12V ignition down to 5VDC. Read about here:
Yes.
I have a dead/rusty connection on the pin on the circuit board inside the fuel gauge for the bar.
I am only seeing 3 volts or so there and if I twist it I will get the 5 volts and things work for a real short time.
My gas gauge reads 2/3 at full and my temp gauge reads just at the cold when fully warmed up.
Here is a good link on the gauge wiring:
snipped-for-privacy@columbus.rr.com wrote:
JimG did pass the time by typing:
Wow, that's a scary method for regulating voltages!
Providing it doesn't pull more than 1A you could use a
7805 Voltage Regulator RadioShack 276-1770,If you need some other level, try the 276-1778 model. It requires more bits
Naw, the fuel gauge only has the 12 volt power tag, then the mechanical voltage regulator inside the fuel gauge kicks in and 5 volts goes to both gauges via that strap.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's"L.W.(ßill) Hughes III" wrote:
The jumper is to get the regulated 5V to the temperature gauge. The fuel gauge does not have to work for the temperature to work as long as the regulator works.
-- JimG
80' CJ-7 258 CID 35" BFG MT on 15x10 Centerlines D44 Rear, Dana 30 Front. SOA 4.56 Gears, LockRight F&R Dana 300 w/4:1 & Currie twin sticks Warn X8000i w/ dual batteries
I made a voltage regulator that could handle 7 amps and tried that. Then I figured out I have an internal bad connection in the fuel gauge...
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'sBut isn't there only one hot wire going to the fuel gauge? And then if that wire somehow does not get juice, it doesn't jump over to the temp gauge,..is that a correct assumption?? thanks Allen
Yes.
Mike
snipped-for-privacy@columbus.rr.com wrote:
You are correct there has to be 12V there for the regulator to work.
JimG
So juice going to the fuel gauge could somehow not get to the temp gauge if there is a malfunction in the fuel gauge correct? Allen
Not necessarily... the 12V at the fuel gauge terminal I provides input to the regulator. Do you have a volt meter? Simply measure for the 12V at fuel gauge I terminal. If it is there, then measure at temperature gauge A terminal for 5V (should be same as fuel gauge terminal A). Does the fuel gauge work? You seem to be stuck on the that.
Are you saying 'both' gauges don't work?
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'ssnipped-for-privacy@columbus.rr.com wrote:
The key does have to be on. Put the meter away until you learn how to use it.
OK, Fuel gauge: If you can get to the pink wire on the fuel sender at the tank (body lift makes this easy), take it loose and touch it to ground, check the gauge, if it goes to full you have a bad sender and the voltage to the gauge is OK. If not then there is no volts at the gauge or the gauge is bad. Usually it is the sender.
Temp gauge: If fuel gauge went to full in above test, continue. (If not then you need to get volts to the fuel/temp gauge before continuing) Pull the wire from the temp. sender at the back of the block and touch it to ground, look at temp gauge. If it goes to hot then you have a bad temp. sender. If not then, the regulator/gauge is bad. Replace the fuel/temp cluster.
JimG
That's about as simple as anyone has come up with. Thanks JimG!!! I'll keep you posted. Allen
Yeah,..right now neither work. I do have a hot lead going to them though (fuel). Allen
To find out if it's a voltage regulator issue, you need to put a multimeter on the strap between the gauges. If you have 5 volts there then you need to look at the senders.
Mike
snipped-for-privacy@columbus.rr.com wrote:
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