You can type here any text you want

Question on field fix harness...

Welcome!

By registering with us, you'll be able to discuss, share and private message with other members of our community.

SignUp Now!

d0n_3d

Boost is good.
Joined
Jul 14, 2001
Messages
4,740
When you have a Casper's field fix harness installed, isn't the whole point of it to bypass the factory dash and supply 12 volts to the back of the alternator from the wastegate solenoid harness? Theoretically can't you run and drive the car without any dash hooked up when you have the field fix installed?

Reason I ask is I'm trying to make this GNX dash work in my 86. The car runs 14 volts with NO field fix harness, stock alternator, stock dash. When I put the field fix harness on with NO other changes, the car still runs at 14 volts. When I take OUT the stock dash completely WITH the field fix harness installed, the car only runs at 11.8 volts. WHY is this? Once you take out the factory dash, I thought the whole reason behind the field fix was to allow for aftermarket dashes that don't hook up to the factory wiring???
 
The alternator will charge as long as you have an alternator warning light hooked up. If the bulb burns out, then you don't have a complete circuit, and the alternator won't charge. That is why that bulb retainer is supposed to have a resistor built into it so that if the bulb burns out, then it will still complete the circuit.
There are a couple of problems with this though. If someone replaces that bulb and puts the wrong retainer back, one without the resistor, and the bulb burns out, the alternator won't charge. Or, as in my case, if your dash isn't making a good connection with the lug, then you won't charge.
This field fix device eliminates these weak points.

Edit: So, if your GNX dash has an alternator light, then that completed the circuit and is why it worked. The field ix is still a good insurance policy.
 
My GNX style cluster does not have any idiot lights. Only turn signals, brights, and 6 gauges (speedo, tach, water, oil, fuel level, and volts). This exact cluster worked fine before on my other car with the exact same field fix harness. I am aware that the factory dash uses the volts light to complete the charging circuit. But I thought the whole idea behind the field fix harness was to BYPASS the factory dash completely. So why am I only getting 11.8 volts when I pull out the stock dash with the field fix??? I'm completely stumped.
 
OK this is F-D up. So I decided to cut the field fix harness plug where it goes to the back of the alternator. I manually spliced in the pink/blk 12V wire from the boost solenoid harness into the F terminal on the plug going to the alt. Fire the car up and STILL 11 volts. WTF! Is the alternator in question now??? I had it tested before and it was fine. Is the regulator just goofy??? I don't understand this at all. I verified with a voltmeter I am getting 12 volts from the pink/blk wire. Please help before I go insane...
 
OK this is F-D up. So I decided to cut the field fix harness plug where it goes to the back of the alternator. I manually spliced in the pink/blk 12V wire from the boost solenoid harness into the F terminal on the plug going to the alt. Fire the car up and STILL 11 volts. WTF! Is the alternator in question now??? I had it tested before and it was fine. Is the regulator just goofy??? I don't understand this at all. I verified with a voltmeter I am getting 12 volts from the pink/blk wire. Please help before I go insane...

You are already insane Don:eek: LOL.
 
I talked to John at Casper's. He says the voltage regulator in the alternator has to be bad. It will charge when using the L terminal (like stock), but will not charge when switching over to the F terminal like I'm trying to do. That would explain why I'm pulling my hair out. I'll update once I swap out alternators.
 
Back
Top