View Full Version : Heater switch and horn problems

06-26-2005, 10:33 PM
I am having some problems with my horn and heater switch. The horn problem seems to be in the contact plate below the steering wheel. When I got it back from the body shop, the horn would sound when the sterring wheel was pushed or pulled. I removed the horn button and contact spring, and it still does it. The contact ring is shorting out some how. Anyone had this problem?

The second electrical problem is in the heater switch. I have power at the switch, but the blower will not work.
If I attach a ground to one of the blower motor terminals the fan will blow on high in the off position, low in the second position and blow a fuse when in the high position. if I take the ground off the blower terminal, the motor will not work at all. I have tried reversing the two wires feeding the switch, but no results. The wiring diagram in the work book is less than clear, and it gives no close pictures of the switch, or even a schematic of it. Any body have any sugestions?
Three hours and five fuses and no further ahead.

06-27-2005, 12:23 AM
I had a similar problem with the horn on my TR4A. it turned out to be the braded wire that jumps across the rubber of the flex joints of the steering shaft. It (the braded wire) was broken but nearly touching so that with motion of the steering column you sometimes made the contact and that let the horn sound. Check those wires, there are two of them.

06-27-2005, 08:53 AM
Thanks Adrio, I will check those wires. By the way, the car is a 70 GT6+ for all those people who might have an insight into my heater problems.


Andy Blackley
06-27-2005, 01:45 PM
Joe: I had a similar problem on my 68 TR250. My problem was that the upper steering column bushing is so worn that the brass contact ring can make contact with the raised boss on the back of the steering wheel hub, thus completing the circuit. The horn push button works to ground the circuit when you push it, and if any part of the wheel or inner column shaft come in contact with the contact ring, which is live all the time, it will make the horn sound.
I did not have this problem until I replaced the aftermarket steering wheel with the stock item. The "boss" on the aftermarket wheel, which is where the inner shaft passes through and has a taper on it, leading to the splines, when viewed from behind, was not as pronounced as that of the stock item. My "expedient solution" (read: bodge)was to wrap a piece of electrical tape around the offending boss to insulate it until such time as I rebuild the column.
If your problem just started after the body work and the steering wheel was not disturbed your problem may be as Adrio described.
Here is a link to a nice on-line wiring diagram for Tr250/6 which is probably similar to that of the GT6: https://www.advanceautowire.com/tr2506.pdf


06-27-2005, 05:01 PM
I just got done fixing my fan switch on my 70 gt6. What I found was the following. The motor ground had been pulled out. The switch was all gummed up. I cleaned the contacts strip with some steel wool and cleaned the bottom of the contact. Then put some electric grease on some it to help protect it and it started working for me again. What I did find at one point was it had some dead spots on the contact board. But if I moved the switch to the right or left it worked. You should have 2 wires coming off the switch make sure they are both good. Good luck. Tom

06-27-2005, 05:21 PM
Thanks Andy and Tom, I will have a look at both tonight and try again.