Electrical problems |
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Electrical problems |
watsonrx13 |
Aug 13 2008, 07:01 PM
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#1
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Advanced Member Group: Members Posts: 2,735 Joined: 18-February 03 From: Plant City, FL Member No.: 312 Region Association: South East States |
I've been trying to track down an electrical problem with my FI and I've found more problems.
1. When I turn on the ignition switch I blow fuse #9. The Haynes manual says that this fuse powers the turn signals, brake lights and back-up lights. Also, I noticed that the buzzer sounds when I turn on the key, regardless of both doors closed or open. Anyway, I disconnected the brake light switch at the brake pedal, all of the wires to the turn signals and disconnected the back-up light wire at the tranny but the fuse still blows, which then stops the buzzer. 2. No power to the coil. I've replaced the ignition switch with another one, but I'm still not getting any power at the coil. I've checked the continuity between the ignition switch and the coil. I have power to all pin #30s on the relay board in the engine compartment. I have power at the large red wire at the ignition switch. I feel that I'm very close to getting this car running, but with these electrical gremlins I'm extremely frustrated...(IMG:style_emoticons/default/mad.gif) Any suggestions and/or guidance would be greatly appreciated.... -- Rob |
904svo |
Aug 13 2008, 08:05 PM
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#2
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904SVO Group: Members Posts: 1,119 Joined: 17-November 05 From: Woodstock,Georgia Member No.: 5,146 |
Try this remove fuse #9, using a volt meter or trouble light check
1. Turn on key, one side of the fuse should have 12 volts on it (Black wires on it) these wires go to the ingition swich and to the relay board which supply power to the coil and other relays. If this is OK check the following 2. Problem must be on the black/yellow wire ( brake switch) or the red/white wires which power the gauges and the emergency flasher switch if you disconnect these wires and reattatched them one at a time you can find out which wire is causing you a problem which you can track down the problem. hope this helps you |
watsonrx13 |
Aug 14 2008, 06:52 AM
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#3
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Advanced Member Group: Members Posts: 2,735 Joined: 18-February 03 From: Plant City, FL Member No.: 312 Region Association: South East States |
Thanks everyone for your replies...
Try this remove fuse #9, using a volt meter or trouble light check 1. Turn on key, one side of the fuse should have 12 volts on it (Black wires on it) these wires go to the ingition swich and to the relay board which supply power to the coil and other relays. If this is OK check the following 2. Problem must be on the black/yellow wire ( brake switch) or the red/white wires which power the gauges and the emergency flasher switch if you disconnect these wires and reattatched them one at a time you can find out which wire is causing you a problem which you can track down the problem. hope this helps you 1. I'll check this circuit and report back later today... 2. I should disconnect the black/yellow wire at the brake switch on the brake pedal? I should disconnect the red/white wires at the head light switch in the dash? I should disconnect the red/white wire at the emergency flasher switch in the dash? What year car is it? Does it have the logic circuit under the passenger seat??? Rich Sorry, it's a '74 2.0l and I've already bypassed the passenger seat circuit... It almost sounds like you might have multiple problems. 904svo's advice sounds pretty good to me. The routing of the power for the coilis really straight forward. from the switch to fuse s9 then back to the relay board. The power does not go through the fuse. It is only a connection point. On the relay board that power should be present on pin 8 of the 14 pin connector, pin 7 of the 12 pin connector and on pin 85 of both the main power and heater blower relays. Take out fuse 9 and work on the coil cct first - it will help keep things a little more simple. Again to simplify things - take the power lead off the coil while you are doing your trouble shooting So, I should take the fuse out of #9, turn on the ignition switch and check power at pin 8 of 14, pin 7 of 12 and pin 85 of relay 74. When I check the pins of the connectors, should I have the connectors installed in the relay board with the cover off or just pull the connectors and check the pins? Should I pull the relay and check the socket or wrap a wire around the pin, reinstall the relay and check power then? sounds like you have a direct short. since the turn/brake lights are in the curcuit, have you messed with the bulbs previous to the problem? a 1156 inserted 180* off will do odd things. how about the 1156 in the 1157 spot or visa-versa? been there, done that, got the t-shirt mike I haven't messed with any of the bulbs, but I did clean up all of the sockets prior to reinstallation.... Something else that I just remembered, all of the light circuits were working well and no issues with the fuses prior to me dropping the engine/tranny. This problem only came up once I reinstalled, so, is it possible that I might have pinched a wire somewhere when I reinstalled the engine? If so, do I need to drop the engine and recheck all of the wire? -- Rob |
orange914 |
Aug 14 2008, 10:51 AM
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#4
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http://5starmediaworks.com/index.html Group: Members Posts: 3,371 Joined: 26-March 05 From: Ceres, California Member No.: 3,818 Region Association: Northern California |
sounds like you have a direct short. since the turn/brake lights are in the curcuit, have you messed with the bulbs previous to the problem? a 1156 inserted 180* off will do odd things. how about the 1156 in the 1157 spot or visa-versa? been there, done that, got the t-shirt mike I haven't messed with any of the bulbs, but I did clean up all of the sockets prior to reinstallation.... Something else that I just remembered, all of the light circuits were working well and no issues with the fuses prior to me dropping the engine/tranny. This problem only came up once I reinstalled, so, is it possible that I might have pinched a wire somewhere when I reinstalled the engine? If so, do I need to drop the engine and recheck all of the wire? -- Rob so if i understand you, you did remove the bulbs to clean the sockets AT the time of the install. if so did you test and confirm good operation of the lights before the problem showed up? i think you've got good advice to trace it back to find where the problem lies, beginning from the start of the power feed to the end of the loop. start from one end or the other, but not somewhere inbetween. i just try to rule out any easy to check, possible oversights (mistakes of recent repairs or pinch possibilities) before digging in. a shorted to ground (pinched wire) is a good posibility if the wires are in the area. an improperly installed or wrong bulb can and/or will direct power to ground, blowing the fuse. by the way, at least the 914's i've seen, seem to corrode in the sockets. when we cleaned ours we used di-electric grease hoping to help preserve the connections, seems to have worked. good luck (IMG:style_emoticons/default/beerchug.gif) |
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