fuse keeps blowing

 

hazard flashers work, but when flashers on, right green indicator arrow does not flash, but the left side does

 

is there a junction to separate the loads on this fuse circuit?

 

what is causing the problem?????

 

btw: digidash

Well the problem is caused by a short in the wiring somewhere but the real question is; where is the short?

 

The dash right turn signal indicator not working may be a clue but it may not be also. That may be just a connection problem in the turn signal switch. It would really help to have some more clues to pin down the area of trouble. Does the fuse blow when a certain thing is turned on or switched? The back up light circuit is a good place to start. Along with the turn signals and BU switch, fuse 10 supplies power to the 4WD selector switch, and power window control relay.

fuse blows when key on, everything off

Is the carpet wet at all on the passenger side?

 

The power window lead runs under the carpet on the passenger side, right under were feet would step. The wire has one of the notorious brass band clamp *junctions* were the wire splits to provide power to each window.

 

It's a real common corrosion point, and will short to ground on the floor pan if there is any moisture in the carpet.

may be a possibility, car has been inside almost 1 year

 

 

also noticed relay above hood release is severely rusted, any idea what it is for?????, btw: bisconected it before trying to find short

summary of findings:

 

upgraded to 15a circuit breaker

 

left = blow

off = blow

right = blow after short delay, tries to flash once, and dash lights go dim before blow

 

just tried with 20a cb.

 

only difference is right tries to "flash" 6 times, but turn signal bulb does not flash

Edited November 15, 200817 yr by subiemech85
add more info

If you haven't checked out what Gloyale said to do I suggest you do that. He has most likely pinpointed the trouble area.

well, here's 1/2 disconnected "relay" with 3 large wires and one small wire, wire colors are black, black with white, black with yellow, and small black

 

will look into this sunday after I wake up

 

after unplugging the relay, the turn signals work

 

relay is in the bracket that holds 4 relays, and supposidbly the turn signal unit, second from the left

Edited November 16, 200817 yr by subiemech85
add more

The relays you describe are for the blower, the left and right headlights, and the rear defogger. Going by the wire colors you gave it sounds like you pulled the relay for the right side headlight. That uses fuse #8, not 10. If the short is cleared by removing that relay then the fuse number is wrong.

well my puzzler got puzzled

 

with either side headlight relay removed, that headlight is about 50% bright, while the other is 100% bright with headlights turned on headlights work normal when both relays are connected

 

while "fuse" #10 is not blown, and park brake set, indicator light is on, but if blown, indicator is off

 

defrost seems to not work, also no indicator

 

4wd solenoids no longer click, and no indicator

 

overhead center lamp does not turn on when door open, but works in on position

 

turbo light no longer continuously on

 

pulling headlight relay no longer allows turn signals to work as did before in previous post

 

all that has happened differently, was AFTER 3 mile test run

 

replaced 3 relays because the tin tops were rusty, one was very bad, even had corroded terminals, it was above the hood release

The headlights should not be getting any power to them with their respective relays pulled out. It also sounds like the turn signals are getting power from the headlight circuit somehow. The combination switch may have a problem or the wiring to it in the steering column. There may be some damaged wires due to the use of the circuit breaker.

When I return back to my weekend home on friday evening, I will try to tackle the problem again.

 

will try using a compass to find the short

 

thanks for the help sofar

The power to the E-brake circuit comes from fuse 12. Something isn't right here. Either you are not stating the correct fuse numbers or there is a major problem in the wiring.

 

I am using a manual for an '88 model but I think there is very little difference in the two, if any.

IIRC it's book 4 electrical for '88

 

all fuse numbers are exactly as illustrated

 

#10 is second from left in middle row

 

That is fuse 10 alright. It appears you have a power circuit that is bridged to another somehow. It may be on the backside of the fuse panel. It also may be in the steering column. If there is a connector near the steering column you could try disconnecting it and see what happens.

The headlights should not be getting any power to them with their respective relays pulled out. It also sounds like the turn signals are getting power from the headlight circuit somehow. The combination switch may have a problem or the wiring to it in the steering column. There may be some damaged wires due to the use of the circuit breaker.

 

No, they ALL do this. I think it's a backflow of voltage through the ground connection or something, but trust me it's completely normal, happens as well when the Headlight fuses blow.

 

I can't tell you how many times someone brings me a car and say's "I've replaced the bulb 3 times and it's still dim" or " the other mechanic say's it needs rewired"

 

Then I change their fuse, watch their jaws drop, and send them on there way.

Just a dumb question but, have you checked all the signal bulbs and connectors for a short or blow?

 

At any rate, We should clarify.

 

Hazards are powered by fuse 5

 

Back up lights, 4wd solenoids, and turns are powered by 10.

 

The one place where both circuits come toghether is at the Flasher unit. Try replacing it and see what happens.

 

And for What it's Worth, the 1/2 connected relay with the 2 black wires and the Black white, and black yellow wires is not part of either circuit as far as I can tell.

 

dome light and parking brake light are on fuse 12

No, they ALL do this.

 

Isn't that the normal dealer service response Gloyale? .....LOL

 

Thanks for info. I do seem to kind of remember something about that now that you bring that up. As far as the wire colors go, the ones the OP mentioned exactly match the colors shown in my FSM for the right side HL.

As far as the wire colors go, the ones the OP mentioned exactly match the colors shown in my FSM for the right side HL.

 

Correct.

 

However neither fuse 12(turn, backup, etc.) nor fuse 5(hazards) should have any connection to the headlight relay or or fuse.

 

This thread is kinuv getting on my nerves, because everyone is jumpinmg around from circuit to circuit, and confusing issues.

 

If fuse 10 is blowing, focus on that circuit.

As far as the wire colors go, the ones the OP mentioned exactly match the colors shown in my FSM for the right side HL.

 

Correct.

 

However neither fuse 10(turn, backup, etc.) nor fuse 5(hazards) should have any connection to the headlight relay or or fuse.

 

This thread is kinuv getting on my nerves, because everyone is jumping around from circuit to circuit, and confusing issues.

 

If fuse 10 is blowing, focus on that circuit.

Correct.

 

However neither fuse 10(turn, backup, etc.) nor fuse 5(hazards) should have any connection to the headlight relay or or fuse.

 

This thread is kinuv getting on my nerves, because everyone is jumping around from circuit to circuit, and confusing issues.

 

If fuse 10 is blowing, focus on that circuit.

 

I totally agree with you Gloyale. I basically stated the same thing in my earlier posts. But statements made by the OP made things sound like some power circuits were bridged somewhere that should not have been. For instance, in one post he stated that by pulling out the right side headlight relay, it allowed the turn signals work.

Edited November 19, 200817 yr by Cougar

I am only trying to post info that will make solving the issue easier, it is also getting on my nerves

 

decided to disconnect EVERY connecter until the issue goes away

 

after disconnecting 5 relays, and many connecters, finally one made a difference

 

listed in manual as F65 white, 21 pin, connecting to i6 of instrument panel wiring harness, 7 across and 3 down behind fuse box and on same bracket as the connectors F66 and F67 page 9 section 6-3 fig. 10 front wiring harness MPFI model

 

the offending wire is in position #10, has single green wire, no stripes

 

car built 2/87

 

using book printed july '87

Well it looks like we can literally be on the 'same page' with the manuals as I have the same one as you. If I am following your last post correctly you stated that pin 10(?) of connector F65 seems to be the wire path the problem is on. If that is correct check out page 81 of the same section and look what the wire ties to, the power to the turn signal & hazard unit and the hazard switch. Try disconnecting the turn siganal & hazard unit and see if that clears the short when things are connected as they should be.

Edited November 22, 200817 yr by Cougar

with turn singal connector disconnected and pin # 10 connected, the fuse blows

 

also noticed when flashers are on the right side is dimmer than the left

 

One problem that is consistent is the 4wd selector switch does nothing, but it did work the one time the signals worked when the headlight relay was removed

 

back-up light does work

Well apparently the turn signal path is ok and the short is on another leg. Since the 4WD selector isn't working then that may be the path the short is on. If you have an ohmmeter I would suggest you measure between the protected side of fuse #10 and ground and see what the resistance is. It will most likely be less than 1 ohm. Disconnect connectors at suspected trouble areas and see if the resistance goes up a little bit. The path to the fault should be on the last connector you disconnected.