Ignition switch fuse keeps blowing
Discussion
The 25amp igntion switch fuse keeps blowing. I have blown 3 fuses already!
Anybody any ideas why? Basically I try to start the car and after a couple of turns of the starter motor the fuse blows. Could it be condensation from the car being outside under a cover.
Its a 94 Chimaera
Cheers
Alex
>>> Edited by alex200mph on Friday 17th December 10:14
Anybody any ideas why? Basically I try to start the car and after a couple of turns of the starter motor the fuse blows. Could it be condensation from the car being outside under a cover.
Its a 94 Chimaera
Cheers
Alex
>>> Edited by alex200mph on Friday 17th December 10:14
Sounds like you have a short somewhere (master of pointing out the bleedin obvious). I once had damaged wiring by the reverse switch on the side of the gearbox (worn through the insulation where it was rubbing) which blew fuses fairly regularly until fixed, but not as consistently as yours. But it is a candidate, because (on mine at least) it is live off the ignition switch. There are lots of other things powered off the ignition, if any of these were at fault and had the wrong rating fuse fitted they might take out the maion fuse rather than their own fuse.
Is it only if you actually crank the motor over, or any time you leave the ignition on? This might give a clue as to where the short is.
Is it only if you actually crank the motor over, or any time you leave the ignition on? This might give a clue as to where the short is.
I had a similar problem with my old S3. The wiring looms are cut and spliced to fit the alarm & immobiliser (by the factory?) and the soldered joints simply taped over.
In the interveening years as the adhesive on the insulation tape deteriorated all manner of crap & damp built up under the insulation tape. Eventually this was sufficient to allow shorting to earth and the ignition fuse would blow.
(Problem found after three attempts by the AA patrolman - was mightliy impressed at the time)
Problem was solved by stripping the insulation tape off, cleaning the wiring and retaping. Then had the alarm system thoroughly checked out by a professional.
I suggest that you have a look for any wiring that seems badly taped or open to the elements.
In the interveening years as the adhesive on the insulation tape deteriorated all manner of crap & damp built up under the insulation tape. Eventually this was sufficient to allow shorting to earth and the ignition fuse would blow.
(Problem found after three attempts by the AA patrolman - was mightliy impressed at the time)
Problem was solved by stripping the insulation tape off, cleaning the wiring and retaping. Then had the alarm system thoroughly checked out by a professional.
I suggest that you have a look for any wiring that seems badly taped or open to the elements.
You might spot the problem if you try cranking the car over in the dark. Get someone else to turn the ignition whilst you watch under the bonnet. You might see a spark - just before the fuse blows!
Obviously it goes without saying that you need to be carefull. If a fuse is blowing that quickly, you have an almost dead short somewhere. Yo don't want your pride and joy going up in smoke.
Obviously it goes without saying that you need to be carefull. If a fuse is blowing that quickly, you have an almost dead short somewhere. Yo don't want your pride and joy going up in smoke.
I had the exact same problem AFTER replacing the starter motor.
The one supplied drew too much current on the trigger input and blew the fuse.
Called the company that I had got the replacment from and they changed it (ironically to the one that I had given them in exchange... which they had now re-conditioned). Works every time now without any problems.
The easy way to spot the difference is the size of the trigger spade connector. It should be a small one (blue or possibly red if you buy one from a spares place).
If it is a bigger one (yellow from a spares place) then it may be the wrong starter motor which pulls too much trigger current.
The one supplied drew too much current on the trigger input and blew the fuse.
Called the company that I had got the replacment from and they changed it (ironically to the one that I had given them in exchange... which they had now re-conditioned). Works every time now without any problems.
The easy way to spot the difference is the size of the trigger spade connector. It should be a small one (blue or possibly red if you buy one from a spares place).
If it is a bigger one (yellow from a spares place) then it may be the wrong starter motor which pulls too much trigger current.
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