Volt gauge is all the way to the left how do i fix

Fuses? Blown fusible link? Most gauges work by getting 12 volts from the ignition switch when on, and getting a ground from the sender. Often the 12 volt supply wire goes to more than one so if dead, both will fail. If you have a wiring diagram, you might find which wire to cluster should be hot, and trace it backward to find the issue. Easier to check for ignition switch feed first.

you may need to replace the sending unit

Battery light goes off and on. Volt gauge goes well below half. You have a charging system problem . Voltage regulator or brushes worn out . do you know what these are ? This charging system is computer controlled .
What color wire's in connector you can't find where it hooks to. an how many wires .
By the way I have a ignition interlock on the car.????? so ! Has nothing to do with alternator problem . Can you lock the ignition switch an pull the key out ? Can you move the shifter out of park ?

It sounds like you might have a poor ground connection somewhere. You can test each individual gauge for full travel by grounding the wire the goes the each gauges individual sender. In other words to check the temp gauge, ground the wire that goes to the temp sender. The temp sender is in the left cylinder head between the #1 and #2 spark plug ( looks like a brass pipe plug with a single wire coming from it) if you ground the wire with the key on (engine off) the gauge should go to the end of the scale (hot) with the wire off it should go to full cold. You can do this with the gas gauge too but not the amp gauge or volt meter. If the volt gauge is reading low (if it has one) and you know that battery voltage is good (don't guess, measure with a multi-meter) there has to be a poor connection somewhere.

How to repair GM Instrument Cluster Speedometer Gauge Stepper

altenatorrrr

With the jeep running put a volt meter on the battery and it should be reading above 13 volts if not replace the altinator it isn't charging.You can check the fuse for the altinator first if not charging but most likely the altinator is bad.

MAKE SURE COOLANT NOT LOW.IF ALL IS GOOD.THE DEALERSHIP HAS TO FIX SOUND LIKE PROBLEMS IN THE AUXILIARY HVAC CONTROL MODULE.IT CONTROLS THE HEATER AND AIR DOORS ACTUATOR.THAT COULD BE WHY YOU ARE NOT GETTING HEAT. YOU HAVE A FAULTY CLUSTER IF YOU HAVING SPEEDOMETER AND FUEL GAUGE PROBLEMS.BUT CHECK BATTERY VOLTAGE IT SHOULD BE 12.5 VOLTS WITH ENGINE OFF.13.5 VOLTS TO 14.5 VOLTS WITH ENGINE RUNNING.I HAVE SEEN A BAD AND WEAK BATTERY CAUSE DASH GAUGE PROBLEMS AND CHECK ENGINE LIGHT TO COME ON.IF CAR FAILS THE VOLTS TEST.IF YOU USE A DIGITAL VOLT METER BATTERY WAS NOT 12.5 VOLTS.YOU NEED TO HAVE THE ALTERNATOR AND BATTERY TESTED.YOU CAN GO TO ADVANCE AUTO OR AUTO ZONE.AND SEARS THEY WILL CHECK TO MAKE SURE BATTERY AND ALTERNATOR IS WORKING.THEY WILL DO IT FOR FREE.

sometimes when a battery gets weak it will not properly charge the brain box in return all gauges lights come on and off ,simple fix ,new battery,the brain needs about 11.6 volts to properly work. i had same problems with dodge truck thats what fixed mine

do you know that petrol gauge is a sort of volt meter.there are five things requir to operate it.1st of all see to it that movement of gauge is working.give 1.5v of a battery directly to gauge for amoment if gauge doesn't move change the -ve to +ve even then it doesn't move it means gauge itself is faulty.if it moved look out for a wirewound resistor in fuel tank.if it is open then gauge will not work.if that is good look for voltage across resistor normally 12v are given.if 12 volts are there then look out for flot.connect a voltmeter to gauge,move the flot by hand very slowly and see if the varition in volt meter if it is not there then look out for connecting wires from gauge to fuel tank.i think you can do it now