duff electrics, HELP
Discussion
Have gone away for the weekend and after driving car in rain this morning have developed a problem not expereinced before.
on starting the car to go out again this afternoon I found that the alternator charging light does not go out, fan belt ok, my indicators are dead and the clocks, except speedo and rev counter, are not working.I checked the connections under the bonnet where the loom goes off to the front lights either side of the radiator, via a connector block connection, and found the green wire on both sides coroded and loose, repaired and reconnected I replaced the blown fuse and all was back to normal,but having used the car this evening after initial start up,all the original problems have returned.
any advice or ideas greatly appreciated as I have to travel home sunday pm
on starting the car to go out again this afternoon I found that the alternator charging light does not go out, fan belt ok, my indicators are dead and the clocks, except speedo and rev counter, are not working.I checked the connections under the bonnet where the loom goes off to the front lights either side of the radiator, via a connector block connection, and found the green wire on both sides coroded and loose, repaired and reconnected I replaced the blown fuse and all was back to normal,but having used the car this evening after initial start up,all the original problems have returned.
any advice or ideas greatly appreciated as I have to travel home sunday pm
There are 2 types of "shorts" short to earth & cross shorts. Cross short means that 2 circiuts are effected, i.e if you turn on wipers the horn blows etc. Shorts can happen anywhere, inside connectors, in the middle of a wire & so on.
You have already narrowed it down to the circuit that is effected by discovering the fuse that blew. replace the fuse again & try using the items on the circuit one at a time, checking the fuse after each attempt. if the fuse doesn't blow. then wiggle the wires and connectors for that circuit checking the fuse after each attempt.
The easiest way to find a short on a long wire is to pass a compass along it. Since all wires carrying electricity have a small amount of electro-magnetism surrounding them the compass when held near will read North & as soon as the compass passes the short the needle will move off of north.
A wiring schematic of the car will help greatly & concentrate on places the wires are most likely to get chaffed i.e. connectors, where they are tied down, where they pass through the firewall etc.
Hope this helps,
Trooper2.
Edited for spelling
>> Edited by Trooper2 on Saturday 5th February 21:45
You have already narrowed it down to the circuit that is effected by discovering the fuse that blew. replace the fuse again & try using the items on the circuit one at a time, checking the fuse after each attempt. if the fuse doesn't blow. then wiggle the wires and connectors for that circuit checking the fuse after each attempt.
The easiest way to find a short on a long wire is to pass a compass along it. Since all wires carrying electricity have a small amount of electro-magnetism surrounding them the compass when held near will read North & as soon as the compass passes the short the needle will move off of north.
A wiring schematic of the car will help greatly & concentrate on places the wires are most likely to get chaffed i.e. connectors, where they are tied down, where they pass through the firewall etc.
Hope this helps,
Trooper2.
Edited for spelling
>> Edited by Trooper2 on Saturday 5th February 21:45
Voltage reading OK?
Dials not working would imply either a wiring fault/blown fuse on the -ve side, or an earth fault. Given the weather, I'd be inclined to suspect an earth fault. On mine most circuits are earthed onto a stud at the front of the passenger side outrigger, behind the NSF wheel under the bonnet (from memory the wheel arch liner hides this). No charge warning implies either a big drop on the +12 switched ignition circuit, or the alternator overcharging or not charging. The voltage gauge reading ought to tell you whether the alternator is charging or not.
Dials not working would imply either a wiring fault/blown fuse on the -ve side, or an earth fault. Given the weather, I'd be inclined to suspect an earth fault. On mine most circuits are earthed onto a stud at the front of the passenger side outrigger, behind the NSF wheel under the bonnet (from memory the wheel arch liner hides this). No charge warning implies either a big drop on the +12 switched ignition circuit, or the alternator overcharging or not charging. The voltage gauge reading ought to tell you whether the alternator is charging or not.
the voltage guage meter is not working as it runs on the same fuse-circiut as the indicators,fuel guage, temp guage, and oil pressure guage.while out this evening I believe that the alternator is still being charged as I was using headlights and heater, with no dimming of lights after 20 minutes use.tomorrow I will check the indicator connections at the front again, the earth you pointed out on the chassis, and the front indicator bulb connectors in case they are wet.
I can`t try disconnecting items to do a trial and error test to eliminate the fault as all the guages are in dash, and hope that it is somethimg outside affected by the weather giving bad earth or connection.
I can`t try disconnecting items to do a trial and error test to eliminate the fault as all the guages are in dash, and hope that it is somethimg outside affected by the weather giving bad earth or connection.
As far as I remember, all the gauges share a common 12v supply from the fuse box, so I don't think testing them individually would show anything. It looks like a fault either on the 12v supply, or earth. It may not be a coincidence that the indicators have gone at the same time, so I'd look for a common cause. Unfortunately the indicators are also ignition switched and share the same earth point so this clue doesn't help much. It feels like I bring this up for almost every electrical problem, but it is worth checking the connector between the ignition switch and the main loom. It's a well known weak point and can overheat and corrode, leading to contact resistance and more overheating etc until it finally melts or catches fire. This can cause a voltage drop on the switched ignition circuit which can make the no-charge warning light glow. If it failed completely you would get a dead car rather than individual circuits not working though. It isn't the whole answer but may be part of it.
Incidentally on the indicator connectors, those Ripault connectors are not designed for exterior use and inevitably corrode and fail. If you're replacing them, I'd recommend you replace the whole lot with a decent weatherproof connector. I use SureSeal connectors, which are hermetically sealed, have a decent current rating and a very compact form factor up to 20 pins.
Incidentally on the indicator connectors, those Ripault connectors are not designed for exterior use and inevitably corrode and fail. If you're replacing them, I'd recommend you replace the whole lot with a decent weatherproof connector. I use SureSeal connectors, which are hermetically sealed, have a decent current rating and a very compact form factor up to 20 pins.
thanks for all the advice.
I hope that I`ve found the to the problem this afternoon, this being that the cigarette lighter, which always rubs against my left leg, had come loose and the live supply I think was frequently earthing out on the voltage guage earth connector, since correcting the loose wire, so far no problems.
the cigarette lighter filament now lives in the glove box!!
at least I`ve also learnt to replace the front light connectors as soon as possible, and found a cracked indicator lense which was full of water.
once again thanks for the help.
I hope that I`ve found the to the problem this afternoon, this being that the cigarette lighter, which always rubs against my left leg, had come loose and the live supply I think was frequently earthing out on the voltage guage earth connector, since correcting the loose wire, so far no problems.
the cigarette lighter filament now lives in the glove box!!
at least I`ve also learnt to replace the front light connectors as soon as possible, and found a cracked indicator lense which was full of water.
once again thanks for the help.
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