lastwgn

Looking for ideas on a curious electrical problem. I have a 54,000 mile 1983 GS. It is completely stock, exactly as it left the factory, including the stereo. I acquired the car last month from the original owner. The problem I am having is that when I turn on the radio, which is an untouched factory unit, the windshield wipers turn on. The electric radio antenna does not work. Ever since I have had the car it has been stuck, about 2/3 of the way up. Looking at the antenna unit itself, it looks absolutely pristine. I know that under the dash there is an antenna relay, which is very close to something called a "control processing unit." The CPU has a relay inside (or something that works like a relay) to control the intermittent function of the wipers. Could the signal the radio is sending to the antenna relay somehow trigger the CPU to run the wipers.

According to the original owner, he was not aware of the problem as he had not driven the car much in the past few years. He never had any electrical work done under the dash, so it is not likely a misplaced wire.

I searched the forum but could not find anything on point, and I am not great with electrical stuff. Any thoughts would be helpful.

mark n

electricity will follow the path of least resistance.It sounds like something is grounded wrong or a pug is crossed or has come loose You can access the radio wires and check the antenia with a ground light or a continuity tester. clip the ground side of the light to a good ground and use the point part to hit the power circuit wire that goes to the antenna motor. I would start with the antenna possably a bad ground there .The electricity will accually back feed if you have power wires crossed .The multi switch could be your culprit.Like I said you need to check each cercuit with the ground light.Get a haynes manual for wire colors and such. Good luck

74RX4

iTrader: (10)

Mazda likes to use switches to interrupt the ground circuit instead of the +12v. Both the power antenna and ww wiper motors receive 12v power whenever the ignition is turned on. The Blue green wire from the radio connects to the antenna relay. When the radio is turned on the wire is grounded. This supplies the ground to the relay which connects the ground to the antenna motor. WW is the same. Turning on the switch connects the motor to ground, turning the wipers on. The only wiper function that is controlled by the Central Processing Unit is the intermittent feature.

When the radio turns the wipers on are they on Intermittent, Low or High speed?
What happens when the wipers are turned on without the radio? Do all the functions work properly?

Sounds like you may have a wire connected incorrectly.

lastwgn

Thanks very much for the input. Very helpful. It sounds like it is going to have to be a matter of tracing through the wires to sort it out. When the radio is off, the wipers work correctly. When the radio is switched on, the wipers run on a standard low speed wipe. From what has been said, it certainly sounds like either a grounding problem, or a crossed wire problem. I guess it will be a day in the garage trying to work the problem. Oh well, a bad day in the garage is better than a good day in the office!!

j9fd3s

iTrader: (3)

if the car's been sitting chances are that the switches are dirty too, or it might just have a funky ground somewhere too.

i would start by cleaning the battery terminals. step 2 is just to cycle the switches a few more times.

patmac6075

iTrader: (26)

Hey all,

I've got all the components (I think) to add cruise control to my '83 GS. I've got a complete stalk w/cruise button, a cruise switch for between the seats, and the big Can w/throttle cable that goes under the hood and hooks to the carb.

Question is, do I just start hooking this stuff up and go? The switch between the seats has a connector that looks like a logical fit....the stalk is a simple replacement and logical hook up (I think).....The Can can't be too hard....assume I need a manifold vacuum...the electrical connectors are right there, and hook up to throttle.... The guy who I bought this from also sent me what looks like a CPU he said it was the cruise control controller (not sure if he sent me the proper part or not) where does this go? Does it replace my current CPU?.

Before I go monkeying around with some pretty important stuff, I was hoping I could get some expert advice.

Sorry....meant to make a new post

FunK73

iTrader: (6)

If you need a hand let me know, i love helping out some local rx7 owners