Any Auto electricians on here ?
Discussion
Just need some advice pls
I have a 91 Fiesta RST and i've lost the ignition lights on the dash. The car turns over but no lights, I've had a good look in the fuses and relays but nothing obvious. Also when the ignition is in what would be the on position there's no spark from the battery when you disconnect and reconnect the terminals which you would expect there to be,
So is there anyway of getting power to the ignition ?
Thanks
I have a 91 Fiesta RST and i've lost the ignition lights on the dash. The car turns over but no lights, I've had a good look in the fuses and relays but nothing obvious. Also when the ignition is in what would be the on position there's no spark from the battery when you disconnect and reconnect the terminals which you would expect there to be,
So is there anyway of getting power to the ignition ?
Thanks
I'm confused. Is this a "car cranks but won't start" problem or just a couple of missing lamps in the dashboard display?
Dodgy immobiliser or related wiring issues as mentioned above is always one possible culprit. Another is a corroded (oxidised) or loose plug-in connector somewhere behind/under the dash. Either way, you need to get your head behind the dash and under the bonnet to check all connectors are secure and see of there's any aftermarket wiring that's been badly spliced into the harness.
Dodgy immobiliser or related wiring issues as mentioned above is always one possible culprit. Another is a corroded (oxidised) or loose plug-in connector somewhere behind/under the dash. Either way, you need to get your head behind the dash and under the bonnet to check all connectors are secure and see of there's any aftermarket wiring that's been badly spliced into the harness.
Ok so that car isn’t too complex.
Pull the ignition barrel cowl off and you’ll see only a few wires.
This is going back 20 years and from memory so forgive me if the colours are a little out.
But basically the fat red on the barrel is power in.
The blue black (sometimes red black I think) is the starter. We know that’s working because it cranks.
The fat black is the ignition switch. On these old cars that’s a +30 feed. You can test to see if this goes hot when you crank. Or just splice between the red and the fat black with a big wire with a 30a fuse in it.
The thin red black or white red is the stereo and clock and stuff. That should go hot when you put the ignition on but go away momentarily when you crank.
If you have power down the fat black then that wire goes to the fuse box up above your right knee. Access isn’t too bad - you can drop it down to play with.
These aftermarket systems the guys refer to really are a pest and they were at their height in this era. I used to earn a living putting stuff right that had been butchered, so it won’t be a surprise if the loom from the barrel to the fuse box has been butchered. If you untape it you may find where people have created “cuts” in the wires to create an immobiliser circuit. If that’s the case then you can take those cuts out and restore the wire.
One thing I can’t remember with the Fiesta was whether the loom went up over the column and behind the clocks before it got to the fuse box. If that’s the case it’s still not a problem obviously - just take the black bezel off the instruments and remove them.
You will need decent access like this to work out what’s happening.
Once you trace back to the fuse box and are sure you’re getting juice at that main black feed you will need to follow that forwards into the engine bay, but, I suspect you may find your answer inside the vehicle.
Best of luck if you’d asked me 20 years ago I could have been a lot more help!
Pull the ignition barrel cowl off and you’ll see only a few wires.
This is going back 20 years and from memory so forgive me if the colours are a little out.
But basically the fat red on the barrel is power in.
The blue black (sometimes red black I think) is the starter. We know that’s working because it cranks.
The fat black is the ignition switch. On these old cars that’s a +30 feed. You can test to see if this goes hot when you crank. Or just splice between the red and the fat black with a big wire with a 30a fuse in it.
The thin red black or white red is the stereo and clock and stuff. That should go hot when you put the ignition on but go away momentarily when you crank.
If you have power down the fat black then that wire goes to the fuse box up above your right knee. Access isn’t too bad - you can drop it down to play with.
These aftermarket systems the guys refer to really are a pest and they were at their height in this era. I used to earn a living putting stuff right that had been butchered, so it won’t be a surprise if the loom from the barrel to the fuse box has been butchered. If you untape it you may find where people have created “cuts” in the wires to create an immobiliser circuit. If that’s the case then you can take those cuts out and restore the wire.
One thing I can’t remember with the Fiesta was whether the loom went up over the column and behind the clocks before it got to the fuse box. If that’s the case it’s still not a problem obviously - just take the black bezel off the instruments and remove them.
You will need decent access like this to work out what’s happening.
Once you trace back to the fuse box and are sure you’re getting juice at that main black feed you will need to follow that forwards into the engine bay, but, I suspect you may find your answer inside the vehicle.
Best of luck if you’d asked me 20 years ago I could have been a lot more help!
rockin said:
I'm confused. Is this a "car cranks but won't start" problem or just a couple of missing lamps in the dashboard display?
Dodgy immobiliser or related wiring issues as mentioned above is always one possible culprit. Another is a corroded (oxidised) or loose plug-in connector somewhere behind/under the dash. Either way, you need to get your head behind the dash and under the bonnet to check all connectors are secure and see of there's any aftermarket wiring that's been badly spliced into the harness.
Hi yes car turns over but no lights on the dash. Theres power at the back of the relays but no power at any relays ??Dodgy immobiliser or related wiring issues as mentioned above is always one possible culprit. Another is a corroded (oxidised) or loose plug-in connector somewhere behind/under the dash. Either way, you need to get your head behind the dash and under the bonnet to check all connectors are secure and see of there's any aftermarket wiring that's been badly spliced into the harness.
Power at the barrel
Julian Thompson said:
Ok so that car isn’t too complex.
Pull the ignition barrel cowl off and you’ll see only a few wires.
This is going back 20 years and from memory so forgive me if the colors are a little out.
But basically the fat red on the barrel is power in.
There is power on all wires at the back of the barrel with ignition on and crank wire works but no ignition lights, The black is live at the barrel but not at the other end of the block connector towards the fuse box if that makes sense. There is live power going in to the fuse box but only a few fuses and no relays have any power. It's almost like it's lost a main feed or maybe an earth but I honestly can't see anything amiss
The blue black (sometimes red black I think) is the starter. We know that’s working because it cranks.
The fat black is the ignition switch. On these old cars that’s a +30 feed. You can test to see if this goes hot when you crank. Or just splice between the red and the fat black with a big wire with a 30a fuse in it.
Tried this and makes no difference
The thin red black or white red is the stereo and clock and stuff. That should go hot when you put the ignition on but go away momentarily when you crank.
If you have power down the fat black then that wire goes to the fuse box up above your right knee. Access isn’t too bad - you can drop it down to play with.
These aftermarket systems the guys refer to really are a pest and they were at their height in this era. I used to earn a living putting stuff right that had been butchered, so it won’t be a surprise if the loom from the barrel to the fuse box has been butchered. If you untape it you may find where people have created “cuts” in the wires to create an immobiliser circuit. If that’s the case then you can take those cuts out and restore the wire.
There isn't an alarm fitted and no trace of anything. Car was running then switched it off and no ignition however the ignition loom to the back of the barrel was very hot like something was amiss
One thing I can’t remember with the Fiesta was whether the loom went up over the column and behind the clocks before it got to the fuse box. If that’s the case it’s still not a problem obviously - just take the black bezel off the instruments and remove them.
You will need decent access like this to work out what’s happening.
Once you trace back to the fuse box and are sure you’re getting juice at that main black feed you will need to follow that forwards into the engine bay, but, I suspect you may find your answer inside the vehicle.
Best of luck if you’d asked me 20 years ago I could have been a lot more help!
Pull the ignition barrel cowl off and you’ll see only a few wires.
This is going back 20 years and from memory so forgive me if the colors are a little out.
But basically the fat red on the barrel is power in.
There is power on all wires at the back of the barrel with ignition on and crank wire works but no ignition lights, The black is live at the barrel but not at the other end of the block connector towards the fuse box if that makes sense. There is live power going in to the fuse box but only a few fuses and no relays have any power. It's almost like it's lost a main feed or maybe an earth but I honestly can't see anything amiss
The blue black (sometimes red black I think) is the starter. We know that’s working because it cranks.
The fat black is the ignition switch. On these old cars that’s a +30 feed. You can test to see if this goes hot when you crank. Or just splice between the red and the fat black with a big wire with a 30a fuse in it.
Tried this and makes no difference
The thin red black or white red is the stereo and clock and stuff. That should go hot when you put the ignition on but go away momentarily when you crank.
If you have power down the fat black then that wire goes to the fuse box up above your right knee. Access isn’t too bad - you can drop it down to play with.
These aftermarket systems the guys refer to really are a pest and they were at their height in this era. I used to earn a living putting stuff right that had been butchered, so it won’t be a surprise if the loom from the barrel to the fuse box has been butchered. If you untape it you may find where people have created “cuts” in the wires to create an immobiliser circuit. If that’s the case then you can take those cuts out and restore the wire.
There isn't an alarm fitted and no trace of anything. Car was running then switched it off and no ignition however the ignition loom to the back of the barrel was very hot like something was amiss
One thing I can’t remember with the Fiesta was whether the loom went up over the column and behind the clocks before it got to the fuse box. If that’s the case it’s still not a problem obviously - just take the black bezel off the instruments and remove them.
You will need decent access like this to work out what’s happening.
Once you trace back to the fuse box and are sure you’re getting juice at that main black feed you will need to follow that forwards into the engine bay, but, I suspect you may find your answer inside the vehicle.
Best of luck if you’d asked me 20 years ago I could have been a lot more help!
Hi all
SO the car was runnng ok, then i smelt something that wasn't right. Switched the car off and noticed that the loom behind the ig barrel was getting hot. Once it had cooled down there were no ignition lights on the dash but car would crank over but wouldn't start, no fuel pump priming etc
This started me investigating things and I honestly cant see anything wrong, although there is power going to the rear of the fuse box via the main feed wires but none of the relays have any power at all and only about 3 fuses are working
It seems like it's lost a main live or an earth but I cant see anything
Someones mentioned trying to bridge the ignition relay which i'm going to try later so fingers crossed
SO the car was runnng ok, then i smelt something that wasn't right. Switched the car off and noticed that the loom behind the ig barrel was getting hot. Once it had cooled down there were no ignition lights on the dash but car would crank over but wouldn't start, no fuel pump priming etc
This started me investigating things and I honestly cant see anything wrong, although there is power going to the rear of the fuse box via the main feed wires but none of the relays have any power at all and only about 3 fuses are working
It seems like it's lost a main live or an earth but I cant see anything
Someones mentioned trying to bridge the ignition relay which i'm going to try later so fingers crossed
Hmmm - what you've got there, especially the smell, sounds like something "burning out" - either a wire or a component - without the current reaching a high enough level to blow the relevant fuse.
What's tricky is that a wire can fray inside its plastic sheath until it gets very thin and then it burns out invisibly when current is drawn. These can be hard to find. One way to do it is use a voltmeter and a pin.
You can do the same from the other end of the dead wire with your meter set for continuity rather than voltage, but make sure the ignition is off or you might fry your meter.
This sort of problem most often occurs where something is moving quite a lot, such as a boot hinge or door hinge, but can crop up through old age and tiny movements of something like a steering column if you pull on it while getting in and out of the car or if you drive on bumpy roads.
Again, if you see any aftermarket wiring it should be the first area to check out carefully. Most dodgy of all are the "clamp on" type connectors which often break some strands of wire as well as cutting the plastic sheathing....
What's tricky is that a wire can fray inside its plastic sheath until it gets very thin and then it burns out invisibly when current is drawn. These can be hard to find. One way to do it is use a voltmeter and a pin.
- Connect one side of the voltmeter to a good ground.
- Connect the other side of the voltmeter to a sharp sewing pin.
You can do the same from the other end of the dead wire with your meter set for continuity rather than voltage, but make sure the ignition is off or you might fry your meter.
This sort of problem most often occurs where something is moving quite a lot, such as a boot hinge or door hinge, but can crop up through old age and tiny movements of something like a steering column if you pull on it while getting in and out of the car or if you drive on bumpy roads.
Again, if you see any aftermarket wiring it should be the first area to check out carefully. Most dodgy of all are the "clamp on" type connectors which often break some strands of wire as well as cutting the plastic sheathing....
RetroTed said:
Hi all
SO the car was runnng ok, then i smelt something that wasn't right. Switched the car off and noticed that the loom behind the ig barrel was getting hot. Once it had cooled down there were no ignition lights on the dash but car would crank over but wouldn't start, no fuel pump priming etc
This started me investigating things and I honestly cant see anything wrong, although there is power going to the rear of the fuse box via the main feed wires but none of the relays have any power at all and only about 3 fuses are working
It seems like it's lost a main live or an earth but I cant see anything
Someones mentioned trying to bridge the ignition relay which i'm going to try later so fingers crossed
I would advise against bridging anything. Obviously there's a fault in the circuit. If you have an emergency and need to get it home you could potentially bypass whatever part of the circuit has failed as a temporary bodge. Once you're home you need to work out what has actually failed, and fix it.SO the car was runnng ok, then i smelt something that wasn't right. Switched the car off and noticed that the loom behind the ig barrel was getting hot. Once it had cooled down there were no ignition lights on the dash but car would crank over but wouldn't start, no fuel pump priming etc
This started me investigating things and I honestly cant see anything wrong, although there is power going to the rear of the fuse box via the main feed wires but none of the relays have any power at all and only about 3 fuses are working
It seems like it's lost a main live or an earth but I cant see anything
Someones mentioned trying to bridge the ignition relay which i'm going to try later so fingers crossed
It looks as if the switched ignition circuit has failed. You say the wiring was hot. That could be caused by a poor connection or damaged wire causing resistance where it was getting hot, or a fault elsewhere which caused the circuit to draw more current than it was designed for. Given that it has now failed, the logical next step is to follow the voltage from the ignition switch until you find where the circuit is broken. It might be a blown fuse, failed relay, internal failure within the fusebox itself, or even a burned out wire. If the failure was caused by an overload you need to fix the reason for the overload as well as repair the immediate damage.
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