I have a 97 disco V8i. The brake fuse keeps blowing. I have disconnected the brake lights including the the third brake light and it still blows fuses. Is there a relay or solonide that could be shorted? The signals work fine and the fuse only blows when I step on the brake peddle.
Brake fuse blown
- Thread starter raymor
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Chongo
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Brake fuse blown
I have a 97 disco V8i. The brake fuse keeps blowing. I have disconnected the brake lights including the the third brake light and it still blows fuses. Is there a relay or solonide that could be shorted? The signals work fine and the fuse only blows when I step on the brake peddle.
Hello raymor,
Probably the fastest way to cure this is not to step on the brake pedal…..lol
On a more serious note, the power wire leaving the brake switch is obviously shorting to ground. And yes, the short could be in the steering column.
This is where your detective, and deductive reasoning abilities are needed.
The brake system only operates the 2 rear lights and is fed by your foot on the pedal completing the circuit to the light from the battery.
What I do is disconnect the 12 volt battery, and get a 9 volt milliamp battery, hook the negative side to ground, and the positive side to a test light and the other end of the test light to the brake switch wire that is not going to the battery, but to the rear lights. The reason I like the small 9 volt milliamp battery is that it won’t short any system out if you goof. Another neat thing is that when you hook it up the test light will be on, then you can start unplugging wires and bulbs etc. when the light goes out, that is the wire, bulb or system that is shorted.
Of course it’s easier to type it than fix it, but this should send you on your way to finding it by yourself.
Any questions, please post them someone will return your posts soon.
Best wishes……………. Chongo
I have a 97 disco V8i. The brake fuse keeps blowing. I have disconnected the brake lights including the the third brake light and it still blows fuses. Is there a relay or solonide that could be shorted? The signals work fine and the fuse only blows when I step on the brake peddle.
Hello raymor,
Probably the fastest way to cure this is not to step on the brake pedal…..lol
On a more serious note, the power wire leaving the brake switch is obviously shorting to ground. And yes, the short could be in the steering column.
This is where your detective, and deductive reasoning abilities are needed.
The brake system only operates the 2 rear lights and is fed by your foot on the pedal completing the circuit to the light from the battery.
What I do is disconnect the 12 volt battery, and get a 9 volt milliamp battery, hook the negative side to ground, and the positive side to a test light and the other end of the test light to the brake switch wire that is not going to the battery, but to the rear lights. The reason I like the small 9 volt milliamp battery is that it won’t short any system out if you goof. Another neat thing is that when you hook it up the test light will be on, then you can start unplugging wires and bulbs etc. when the light goes out, that is the wire, bulb or system that is shorted.
Of course it’s easier to type it than fix it, but this should send you on your way to finding it by yourself.
Any questions, please post them someone will return your posts soon.
Best wishes……………. Chongo
Thanks Chongo. Sounds like a neat way to trouble shoot the problem. Right now I have all brake likes out of the circuit that is why I was wondering it there are any relays/solonoids in that circuit. I guess it could be a harness problem I'll check it out today and let you know how it turns out.
Brake fuse blown
I have a 97 disco V8i. The brake fuse keeps blowing. I have disconnected the brake lights including the the third brake light and it still blows fuses. Is there a relay or solonide that could be shorted? The signals work fine and the fuse only blows when I step on the brake peddle.
Hello raymor,
Probably the fastest way to cure this is not to step on the brake pedal…..lol
On a more serious note, the power wire leaving the brake switch is obviously shorting to ground. And yes, the short could be in the steering column.
This is where your detective, and deductive reasoning abilities are needed.
The brake system only operates the 2 rear lights and is fed by your foot on the pedal completing the circuit to the light from the battery.
What I do is disconnect the 12 volt battery, and get a 9 volt milliamp battery, hook the negative side to ground, and the positive side to a test light and the other end of the test light to the brake switch wire that is not going to the battery, but to the rear lights. The reason I like the small 9 volt milliamp battery is that it won’t short any system out if you goof. Another neat thing is that when you hook it up the test light will be on, then you can start unplugging wires and bulbs etc. when the light goes out, that is the wire, bulb or system that is shorted.
Of course it’s easier to type it than fix it, but this should send you on your way to finding it by yourself.
Any questions, please post them someone will return your posts soon.
Best wishes……………. Chongo
the rear stoplights may be shorting, try unplugging them & the wires @ rear window High stoplight.
then see if it blows the fuse, I doubt it's your shifter solenoid.
if the fuse doen't blow, try connecting lights until it does
the third (high) brakelight has a habit of shorting to the rear defogger circuit.
did you pull the wires at the back window for the high light?
inspect them as well, just a thought.
luck,greg
then see if it blows the fuse, I doubt it's your shifter solenoid.
if the fuse doen't blow, try connecting lights until it does
the third (high) brakelight has a habit of shorting to the rear defogger circuit.
did you pull the wires at the back window for the high light?
inspect them as well, just a thought.
luck,greg
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Hi Greg, I had all lights disconnected including the high one. Yesterday went out and checked the fuse for the brake switch. Used an ohmmeter and found one end of the fuse was very close to being shorted to ground like less than 1 ohm to ground. This problem seems to come and go lately that is why I was thinking some sort of relay or solonoid as when it is working right I can hear them click on when stepping on the brake, but no click when there is some sort of short.
Today I found that the Green/purple wire going to the brake lights is shorted to ground. Does anyone know where the harness runs or should I just cut the wire and run a new one? I have all the lights disconnected so the short is in the harness somewhere..
I'm not sure, but something tells me that they run back inside next to the door sill. (driver's side)
If you look @ the left taillight plug, isn't there a 2nd plug there that may come from the front?
if so, unplug that & recheck your gr/wt for short.
if it's gone, then that helps narrow it down.
also, search for "bad fusebox" -- that may give you some hints
luck,greg
If you look @ the left taillight plug, isn't there a 2nd plug there that may come from the front?
if so, unplug that & recheck your gr/wt for short.
if it's gone, then that helps narrow it down.
also, search for "bad fusebox" -- that may give you some hints
luck,greg
Hi Greg, I did not see a plug back there, but the harness runs on that side. I will check that out today. I have found that it is the Green/purple wire that runs from the brake switch to the rear brake lights that is shorted to ground.
yup, I was under mine today, I noticed a major bundle on outside of frame rail driver's side
I hate to say cut the shield in the middle, find the wire, cut it, see which end is grounded.
You did unplug the light housings (mine was shorted randomly pass side brake bulb holder, gave me fits)
luck,greg
I hate to say cut the shield in the middle, find the wire, cut it, see which end is grounded.
You did unplug the light housings (mine was shorted randomly pass side brake bulb holder, gave me fits)
luck,greg
Yes I have all the lights disconnected as I had the same thing you had with the bulbs shorting out a couple years ago. Are you saying the the wiring bundle is running outside of the car. If so I did not check that out but will do tomorrow. I was thinking of cutting the Green/purple wire near the brake lights to find out whether it is a problem up front or at the back of the truck.
