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MG MGB Technical - Another electrical gremlin

Ok, after 1 month of resurrecting my latest addition, a 1978 B, I found another electrical issue. When the car is running, the parking lights come are on. When the shut off, the lights go out, but still will work with the switch on the column. This in addition to the turn signals operating with the key off. (this was discussed in an earlier post). I can't find any additions to the wiring anywhere, (jumpers, etc) The hazzard switch was trashed and I unplugged it and removed it from the dash.(searching for one as we speak). Any ideas ??? I got an enlarged wiring schematic and it appears that all the wiring is correct.
Douglas Martin

Douglas;; If the hazard switch is removed you should not be able to have any directional lights. Note that there are six posts on the switch with four close together and two side by side but seperate, The two posts should have green wires going to them and when the hazadrd switch is in the off position the two green are connected internally by the switch to complete the directional light circuit.I suspect your problem could be in that area of the wiring harness.
Sandy Sanders
Sandy Sanders

The parking lights and turn signals things sound like incorrect fusebox orientation or connections. Correctly orientated the fusebox has the front of the top two fuses connected together internally. The connections should be brown on the bottom front, purple on the bottom rear, white or white/brown on the 2nd up front, green on the 2nd up rear, a single red/green on the third up front or top front, two reds on the 3rd up rear, and another two reds on the top rear.

The red/green can be on either the 3rd or top fuses at the front, and it doesn't really matter which reds are on the top two rears.

If the turn signals work even though the hazard switch is unplugged, and there isn't a jumper between the two greens in the connector, then there *must* be additional wiring and/or connections elsewhere, in which case all bets are off.
Paul Hunt 2

Something is not wired correctly. headlight switch gets power from the brown wire directly wired to the starter. Red/green wire goes from the headlight switch to the fuse box, then to the parking lights. The wiring for the parking lights and headlights do not go through the ignition switch.

Starting with the battery, you are going to have to check all the circuits to make sure they are connected properly. Use a meter or a test light to make sure that the circuits are active or inactive when they are suppose to be. Use a continuity tester on the fuse box to determine its correct orientation.
Kimberly

I agree with Sandy. You can still have your turn signals working through the iginition switch if you put a jumper between the two green wires. If I remember correctly, one of the wires in the middle of the six posts brings power to the hazard circuit directly from the starter solenoid (hot). If you connected this wire to the turn signal circuit, I would expect your signals to work whether or not the ignition was on.

I've not heard of a switch on the steering column that operates the parking lights. My 72 B has a two position rocker switch on the dash for the parking and headlights. I assumed that the later models were the same. If all of the wires in the fuse box are on the right fuses (lights on the two top fuses), I would check just behind the fuse box (toward the firewall) where the front, rear, and dash wiring harnesses all come together to see if anything got crossed there.
glq Greg

Read Paul Hunt's reply again. Check the rear of the fuse box to see if the link is as he describes. If you have the fuse box installed with the link at the bottom and wire the box normally you will get lots of strange electrical problems. Don't ask me how I know.

Clifton
Clifton Gordon

Thanks for all the replies. I found a wire on the wrong terminal at the fuse box. That fixed the park light problem. Now, the turn signals are another issue. Somehow a constant 12 volts is getting into the circuit, the signals work with the hazzard switch unplugged. These problems are what keeps me (in)sane.
Of course if I was of sound mind, I'd probably own a domestic econobox.
Douglas Martin

This thread was discussed between 27/06/2006 and 28/06/2006

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