Headlight Fuse Issues
- Thread starter Doc
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I just went out and pulled my parking light out and checked polarity with the parking lights on, the green is + and the white/black is ground,
When they connected this ground to the positive side of the headlights with the headlights not powered (headlight relay opened) nothing should have happened, if it were to get powered (headlight relay closing) is would have been a direct short and would have blown the LH headlight fuse (not the tail light fuse that was blowing on your truck when it was hooked up like this) something has been changed,
Could you do the same test? Pull the plug of the parking light and test the vehicle side of the plug, with the parking lights on your test lamp is suppose to light when connected between the green wire and the neg post of the battery and also between the positive post white/black, perhaps at some point someone reversed the two if so it will be the opposite of above, not sure why someone would do that, but if it is reversed that would explain why it worked to turn on your headlights and blew the taillight fuse
Also might be worth side to pull the other parking light and see if there is any tampering there also,
When they connected this ground to the positive side of the headlights with the headlights not powered (headlight relay opened) nothing should have happened, if it were to get powered (headlight relay closing) is would have been a direct short and would have blown the LH headlight fuse (not the tail light fuse that was blowing on your truck when it was hooked up like this) something has been changed,
Could you do the same test? Pull the plug of the parking light and test the vehicle side of the plug, with the parking lights on your test lamp is suppose to light when connected between the green wire and the neg post of the battery and also between the positive post white/black, perhaps at some point someone reversed the two if so it will be the opposite of above, not sure why someone would do that, but if it is reversed that would explain why it worked to turn on your headlights and blew the taillight fuse
Also might be worth side to pull the other parking light and see if there is any tampering there also,
- Thread starter
- #63
RavenTai, I went out to the truck and discovered something.
I'm an idiot.
You were right. They DID tap into the green wire, not the black and white one.
I was confused because there is electrical tape on both wires, one of which is mine, the other is PO stuff. The Green wire was my tape, so that was the wire that they were tapped into, they must have first tried to tap into the ground wire, blew the fuse, taped it up- and moved to the green wire.
Sorry I mislead you there for a while.
Anyway- The shunt was from the red wire with blue stripe to the solid green wire of the marker light.
I'll just go back and edit my previous posts....
I'm an idiot.
You were right. They DID tap into the green wire, not the black and white one.
I was confused because there is electrical tape on both wires, one of which is mine, the other is PO stuff. The Green wire was my tape, so that was the wire that they were tapped into, they must have first tried to tap into the ground wire, blew the fuse, taped it up- and moved to the green wire.
Sorry I mislead you there for a while.
Anyway- The shunt was from the red wire with blue stripe to the solid green wire of the marker light.
I'll just go back and edit my previous posts....
dont sweat it, it is easy to get confused, I am glad though cause that would have blown my whole idea of what was going on in your truck, I was about to be lost if they had taped into ground, gotta go get dinner I'll post more later tonight
Ok back on track,
As earlier I think your problem is on the red/white somewhere between pin 11 on the large connector next to the fuse box (EA1) and the splice in the dash E12 ( I1 on the 96 ewd )
Could be:
1. The female connector pin 11 on the EA1 next to the fuse box, but you did not see any corrosion or any other damage ,
2. Could be damage inside the female side of EA1 where you could not see where it connects to the red/white wire
3. The red and white wire could be damaged in the harness along the top of the fender to the firewall, not likely but easiest to check.
4. Red/white wire could be damaged from where it passes through the firewall and on to the E12 splice, this would difficult to get to
5. E12 splice could be damaged (also difficult to get to)
It may be a good idea to start with the harness along the top of the fender, take it out of the tape and split loom so you can inspect the length of the red/white wire, this is easiest to get to,
there should also be a way to release the female pin11 from the connector and pull it out (from the connector side probably) once there is some slack to work with and examine the connection, but I have never tried to release these Toyota water proof connectors, if you dotn know ahead of time it is easy to bugger up the connection
Before you go with the following steps (wire damge and dash teardown) I would like to get to the switch connector on my cruiser and make sure that grounding pin 13 and 14 on my truck make the headlights come on and that we have the right connector and pin-out, I am going to try to do this monday night
If the under hood stuff checks out before going in the dash you could try a slightly destructive test by piercing the red and white wire with a sewing pin (trying to damage as few strands as possible) and then short the sewing pin to neg post, if the low beams come on everything under the hood is OK and dash has to come apart
As earlier I think your problem is on the red/white somewhere between pin 11 on the large connector next to the fuse box (EA1) and the splice in the dash E12 ( I1 on the 96 ewd )
Could be:
1. The female connector pin 11 on the EA1 next to the fuse box, but you did not see any corrosion or any other damage ,
2. Could be damage inside the female side of EA1 where you could not see where it connects to the red/white wire
3. The red and white wire could be damaged in the harness along the top of the fender to the firewall, not likely but easiest to check.
4. Red/white wire could be damaged from where it passes through the firewall and on to the E12 splice, this would difficult to get to
5. E12 splice could be damaged (also difficult to get to)
It may be a good idea to start with the harness along the top of the fender, take it out of the tape and split loom so you can inspect the length of the red/white wire, this is easiest to get to,
there should also be a way to release the female pin11 from the connector and pull it out (from the connector side probably) once there is some slack to work with and examine the connection, but I have never tried to release these Toyota water proof connectors, if you dotn know ahead of time it is easy to bugger up the connection
Before you go with the following steps (wire damge and dash teardown) I would like to get to the switch connector on my cruiser and make sure that grounding pin 13 and 14 on my truck make the headlights come on and that we have the right connector and pin-out, I am going to try to do this monday night
If the under hood stuff checks out before going in the dash you could try a slightly destructive test by piercing the red and white wire with a sewing pin (trying to damage as few strands as possible) and then short the sewing pin to neg post, if the low beams come on everything under the hood is OK and dash has to come apart
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Doc, pulled my kick pannel off and shorted pin 13 and 14 to pin 11 (ground) both turn the low beams on without parking lights as expected, what was not expected is it does it with the both on or off,
that confirms that your problem lies in the harness
I took a look for the harness and it comes in much lower in the dash than I expected, looks easier to get to, look at the pics here the harness comes in near the ABS ECU, looks like you woudl have to remove the abs ECU to get access
hope that helps
that confirms that your problem lies in the harness
I took a look for the harness and it comes in much lower in the dash than I expected, looks easier to get to, look at the pics here the harness comes in near the ABS ECU, looks like you woudl have to remove the abs ECU to get access
hope that helps
