78SC heater blower wiring question
#1
Track Day
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After getting an updated alternator installed, the heater blower stopped working. There is power to the motor (blk/yel wire) but the ground wire (brown) is dead. Mechanic thinks there is a bad connection in the harness or a broken wire. When we took a close look at the wire sheath coming to the blower motor connection, I noticed that there was a third ground wire wire( brown) that was clipped off. The mechanic said the cars come from the factory this way. True? any reason not to use this available ground as opposed to finding the break in the original ground wire?
Thanks,
--GREGER
Thanks,
--GREGER
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Burning Brakes
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could you just attach a new wire to the wire thats going to the blower and ground it?not the one thats not attached now, the one thats broken cut it and just attach a new wire and ground it to the panel on the driver side of the motor next to the blower.
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Dear Greger,
Please expand on "updated alternator installed". Does this mean you installed the more powerful alternator or you removed the external regulator and installed an alternator/regulator combination unit ala 1982 models and up.
If you removed the external regulator without checking the earth jumpers that may explain your problem.
You also need the wiring diagrams. The brown wire from the motor is hard connected to a ground stud. Again I am not sure what you mean by "dead wire".
Ciao,
Adrian
964C4
Please expand on "updated alternator installed". Does this mean you installed the more powerful alternator or you removed the external regulator and installed an alternator/regulator combination unit ala 1982 models and up.
If you removed the external regulator without checking the earth jumpers that may explain your problem.
You also need the wiring diagrams. The brown wire from the motor is hard connected to a ground stud. Again I am not sure what you mean by "dead wire".
Ciao,
Adrian
964C4
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hi Adrian
Yes, the combo Alt/Reg model. THe mechanic that did the work supposedly did the wiring hookups correctly, but hey, the blower motor stopped working. The 'dead' wire is a second ground wire (brown) is in the branch of the harness that l that leads to the blower motor. I can't tell where it is attached to earth, but it seems to be a proper connection. I just wanted to make sure it wasn't going to be a problem using it (the second brown wire) instead of the original wire, which has a break. Do you know where I should search for the proper connection? If its inside the engine compartment fuse/relay box, I might tackle it myself. If it is inside the alternator I will take it back to the mechanic and insist that he make it right.
Yes, the combo Alt/Reg model. THe mechanic that did the work supposedly did the wiring hookups correctly, but hey, the blower motor stopped working. The 'dead' wire is a second ground wire (brown) is in the branch of the harness that l that leads to the blower motor. I can't tell where it is attached to earth, but it seems to be a proper connection. I just wanted to make sure it wasn't going to be a problem using it (the second brown wire) instead of the original wire, which has a break. Do you know where I should search for the proper connection? If its inside the engine compartment fuse/relay box, I might tackle it myself. If it is inside the alternator I will take it back to the mechanic and insist that he make it right.
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Dear Greger,
The ground stud is on the left side of the engine bay. I would just jumper the brown wire to a decent earth using a clip cable and make sure the fan works and then bolt it to the nearest earth stud.
Ciao,
Adrian
964C4
The ground stud is on the left side of the engine bay. I would just jumper the brown wire to a decent earth using a clip cable and make sure the fan works and then bolt it to the nearest earth stud.
Ciao,
Adrian
964C4