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electrical drain and no interior lights

Yes midlife, that is the way it is wired and I will be replacing the wiring shortly. So why does the orange wire drain the battery when hooked up and what is its purpose? Could I have a bad vr? Anyway to check this? Also, why do none of my interior lights or guages work? Could it be the light switch and anyway of checking this?
 
"panteramatt" said:
Yes midlife, that is the way it is wired and I will be replacing the wiring shortly. So why does the orange wire drain the battery when hooked up and what is its purpose? Could I have a bad vr? Anyway to check this? Also, why do none of my interior lights or guages work? Could it be the light switch and anyway of checking this?
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Removing the orange wire may stop the battery drain if the VR itself has welded itself together. It's like points in your starter solenoid and can stick in a mode that sucks current from the battery. Is it hot to the touch at all? You've checked the VR by removal of the plug which stops the current drain; more detailed troubleshooting is available in the Ford Shop Manual but for a $25 part, it ain't worth it!

Why do your interior lights or gauges don't work? First, the gauges get their power from the ACC portion of your ignition switch, which routes power through the Constant Voltage Regulator on the back of the dash cluster, converting 12V to 5 V. It also contains a set of contacts that open and close to give a net average voltage of 5V. It can be broken. Power is then routed through the gauge to the sending unit, where it eventually is grounded. If none of your gauges work, I suspect the ACC power line is not going to the CVR or the CVR is bad.

Interior lights are controlled by a fuse (bottom left, if I remember correctly), but tied directly via the fuse to hot power directly from the battery. The fuse could be bad, or a wire broken somewhere in the circuit.

Neither the interior courtesy lights nor gauges are tied into the VR. It appears to me that you have three distinct problems.
 
Yea Im sure I have a ton of problems. So you recommend me getting a new vr? Recommend a certain one? Imk placing a big order from cj pony parts this weekend and want to get everything I need. What should I check or do to fix the lights? Just need to know what I need to order. I did take the headlight switch out and cleaned it and snaded the contacts but still nothing. I do have lights in the shifter and the ignition.
 
If you can, get an electronic VR. Lights in the shifter and ignition are controlled by a separate circuit than the courtesy lights.

I recommend the entire underhood wiring be replaced. Unfortunately, you'll have to re-pin the firewall connector, as the green block does not come with the light harness.
 
So your saying theres nothing I can check or do? The rest of the wiring doesnt look bad at all just the wiring from the alt to the vr is frigged up.
 
Not a whole lot more to test. The wiring from the alternator to the VR is part of the light harness, and there is also an alternator harness that goes to the alternator from the starter solenoid. If you're ambitious, you can start unwrapping the tape and examine the light harness from the VR area and follow wiring around the radiator support to the alternator area. If you find a splice of some sort, make sure it is connecting the right colored wires together and that any exposed wire strands are kept apart by electrical tape and such.

I'm 98% confident your VR is shot, but it may be your wiring that contributed to that condition.
 
"panteramatt" said:
Thanx a ton. Is $50 too much for an electonic vr?
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Most parts houses have electronic VRs for $15-20. I wouldn't pay $50, unless you need one that looks concours correct.
 
Well Midlife, THANX a ton! You were right. Picked up a vr for $13 at advanced and hooked the orange wire back up and sure nuff, no drain. Why did it run fine without it hooked up though? Seemed to keep the battery charged and stuff too.
 
That line controls the amount of voltage sent to the battery, IIRC. Without that line attached, you'll get full voltage output from the alternator at about 16+V instead of the 14.5V it should receive.

$15 for a simple fix is good! Now tackle the interior lights!
 
Thanx mid, your the man! Already took the switch out and tried cleanin it but that didnt work. Really dont wanna spend $50 to find out thats not the problem. Looked at new wiring under the hood, but $220 for the headlight wiring it a little too steep for me right now. Gonna get the wiring from the alt to the vr for now.
 
Ok, so I tore the dash out tonight and did some testing. I have power going to the courtesy lights but they are all blown. I also noticed that the high beam light in the dash works. I tested the dash plug and the top 3 right side pins light up with my tester and a couple others light up once the ignition is on so I am getting power to the cluster. All the bulbs in the cluster are good also.
 
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