keep blowing the 4th fuse from the right, where to look for cause? Options

[DRPHIL914]

Here is what I lose:
Tach, fuel level, oil temp gauge, volt meter. Then the red alt. Light is on, but car runssmoother, it was not right before that.


This is a 75 2.0. D-jet new coil not long
ago, I have a hotspark module, no issues with it seems to be fine.. Had been running really good.
All lights stay on except I think the brake light, that could be the culprit? . I will recheck that. What else is on this circuit?
I thought tomorrow I would disconnet the fuel level sender, maybe that is the cause?

[JeffBowlsby]

Check to see if your AAR wire is shorting to ground.

[Jeffs9146]

My 5th from the right keeps blowing but I have a 75 with a 3.0L-6 and everything else seems to be working? (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/confused24.gif)

[Mike Bellis]

My 5th from the right keeps blowing but I have a 75 with a 3.0L-6 and everything else seems to be working? (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/confused24.gif)

(IMG:style_emoticons/default/hide.gif)

[Mikey914]

My short was in the rear trunk tail lights - brake if I recall correctly.
Hope it helps

[Jeffs9146]

My 5th from the right keeps blowing but I have a 75 with a 3.0L-6 and everything else seems to be working? (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/confused24.gif)

(IMG:style_emoticons/default/hide.gif)

(IMG:style_emoticons/default/lol-2.gif) (IMG:style_emoticons/default/beerchug.gif) It will get figured out but so far it is eluding me!

[orange914]

My short was in the rear trunk tail lights - brake if I recall correctly.
Hope it helps

if the bulbs were all out and switched back in wrong this will happen... ask me how I know (IMG:style_emoticons/default/smile.gif)

[DRPHIL914]

Check to see if your AAR wire is shorting to ground.

thanks, Jeff I will check that out. had not thought of it - i have not put in the ignition harness i got from you almost 2 months ago,. that might be the deal.

My short was in the rear trunk tail lights - brake if I recall correctly.
Hope it helps

I actually had these short out 2 years ago, had to re-splice and had not been a problem, i looked there, found one of the spades came loose , put it back together, but its still tripping, but i will look closer at the brake lines.

also thought maybe the fuel gauge might be the issue or a wire grounding out behind the gauges, i need to take a look there too, i will have time tonight. i thought about doing this trial an error, disconnect the aar. see if that stops it, then the fuel gauge, . i wish the book showed EVERYTHING that runs on one circuit. crazy how on the fuse panal it shows like 3 things and there are 10, LOL

[Prospectfarms]

Light is on, but car runssmoother, it was not right before that.

Say-again, please. "Car runs better when fuse is blown," i.e., when the short circuit is no longer grounded?

[DRPHIL914]

Light is on, but car runssmoother, it was not right before that.

Say-again, please. "Car runs better when fuse is blown," i.e., when the short circuit is no longer grounded?

i seems like that, but it could be because it was warming up and it tends to be a little rough upon cold start up. i was suspecting my CHT, even though it was a new one put in this winter, or could be the AAR, as it seemed that maybe that new AAR i put in this last winter may not be opening up all the way, so that could do it, plus a short on that would keep that from happneing, causing both issues, fuse and bad start up.

hm. , ----

[TheCabinetmaker]

Check to see if your AAR wire is shorting to ground.

thanks, Jeff I will check that out. had not thought of it - i have not put in the ignition harness i got from you almost 2 months ago,. that might be the deal.

My short was in the rear trunk tail lights - brake if I recall correctly.
Hope it helps

I actually had these short out 2 years ago, had to re-splice and had not been a problem, i looked there, found one of the spades came loose , put it back together, but its still tripping, but i will look closer at the brake lines.

also thought maybe the fuel gauge might be the issue or a wire grounding out behind the gauges, i need to take a look there too, i will have time tonight. i thought about doing this trial an error, disconnect the aar. see if that stops it, then the fuel gauge, . i wish the book showed EVERYTHING that runs on one circuit. crazy how on the fuse panal it shows like 3 things and there are 10, LOL

The aar fuse will interupt the fuel pump, so I doubt thats the problem. Don't know if its on that circuit (too lazy to look it uo right now) but check the wires for the reverse lights at the trans. If they fall on the exhaust or axle it will cause an intermittant short.

[DRPHIL914]

Check to see if your AAR wire is shorting to ground.

thanks, Jeff I will check that out. had not thought of it - i have not put in the ignition harness i got from you almost 2 months ago,. that might be the deal.

My short was in the rear trunk tail lights - brake if I recall correctly.
Hope it helps

I actually had these short out 2 years ago, had to re-splice and had not been a problem, i looked there, found one of the spades came loose , put it back together, but its still tripping, but i will look closer at the brake lines.

also thought maybe the fuel gauge might be the issue or a wire grounding out behind the gauges, i need to take a look there too, i will have time tonight. i thought about doing this trial an error, disconnect the aar. see if that stops it, then the fuel gauge, . i wish the book showed EVERYTHING that runs on one circuit. crazy how on the fuse panal it shows like 3 things and there are 10, LOL

The aar fuse will interupt the fuel pump, so I doubt thats the problem. Don't know if its on that circuit (too lazy to look it uo right now) but check the wires for the reverse lights at the trans. If they fall on the exhaust or axle it will cause an intermittant short.

my reverse lights do not work- never have since ive had the car, so i am assuming the switch is bad, but i have not tried to figure it out, - might be time to do that i guess (IMG:style_emoticons/default/confused24.gif)

[TheCabinetmaker]

The bullet type connectors on the wires at the switch are notorious for falling out. Sometimes the switch can be repaired with a minor adjustment.

[TheCabinetmaker]

Ok, just checked. The reverse lights are on that circuit along with the tail lights and turn signals.

[Prospectfarms]

The aar fuse will interupt the fuel pump

FYI That is supposed to be the way it works, but this year I've seen three instances where the AAR wire grounded without blowing the regulator board fuse. Mine was one of those instances, and it fried my ignition harness including the back up light, tach, oil pressure and FP circuits.

Curt nailed it when he repeated all the quotes: The portion of the WH that affects #9 fuse seems to have some issues on this car. Dr. Phil's, if I were you, I'd install that ignition harness you got from Jeff, check out your back-up light, and run a little continuity testing on the usual suspects ID'd in this thread. I bet you'll solve the fuse problem between one of those.

[DRPHIL914]

The aar fuse will interupt the fuel pump

FYI That is supposed to be the way it works, but this year I've seen three instances where the AAR wire grounded without blowing the regulator board fuse. Mine was one of those instances, and it fried my ignition harness including the back up light, tach, oil pressure and FP circuits.

Curt nailed it when he repeated all the quotes: The portion of the WH that affects #9 fuse seems to have some issues on this car. Dr. Phil's, if I were you, I'd install that ignition harness you got from Jeff, check out your back-up light, and run a little continuity testing on the usual suspects ID'd in this thread. I bet you'll solve the fuse problem between one of those.

thanks for the advice, - since i was going to be pulling the engine and transmission in a week or so anyway- going to the tranny clinic next month and having some jackpoint rust repair done at the same time, i'm just going to pull this thing, - i'm having all the tin powdercoated too, so while it is all out and apart, i will put the new harness on- then i will have new FI and injection harnesses, i will put in all new ground straps, etc. and check that reverse switch., from there i will have to wait till it all goes back together and gets put back in the car, - i also have a new fuse panel upgrade coming from egmann- so i was going to do this as well.

tonight i will check the AAR and couple other things . i just need to drive it to the shop so i can start pulling it this week.

i will keep you posted, and again thanks for the advice!!!!
-

[TheCabinetmaker]

Keep us updated please?

[Tom]

Fuse #9 has nothing to do with the AAR.
AAR is fused off of the rear fuse on the relay panel AND at 25 amps is fused too high. I use an 8 amp for mine as I don't have the heater blower hooked up and no rear window defrost. The wire for the AAR is only good for about 20 amps before becoming so hot it melts surrounding wires, so if you fuse that one at 25 and and your AAR shorts out partially, it can fry the AAR wire and surrounding wires. If you do have the heater blower hooked up, using a 16 amp fuse will be good, but carry a back-up. An alternative is to put an inline fuse at the junction where the AAR wire hooks up to your harness wire and fuse it a 5 amps. Be a crying shame to fry that brand new ignition harness!
Tom

[Prospectfarms]

Fuse #9 has nothing to do with the AAR.

Tom, can you rule it out? True, AAR circuit is not fused at the front, but some of the other components suppled by the ignition harness are. The wires supplying AAR and those components are adjacent, and if they start melting.... Since #9 is 7.5A (I think?) it could (not saying it's likely) blow first in the event of a more massive failure within the harness sheath.

[Tom]

Stuart,
You are right! The tach and oil sensor wire are in that harness and if the AAR wire has melted previously, causing damage to those wires, that could be causing the #9 fuse to blow. Of course by that point I would have expected some report of smoke and bad smell.
Tom