FJ60 HVAC Gremlins

[txnight]

Also posted on Ih8mud.

After a search and reading through four pages of threads I still can't find an explanation for an issue that i'm having. I have also read through the Haynes and the FSM with no luck.

I have completely rewired project cars but this has me truly stumped. Before I completely rip the dash out and scare my wife I'm asking for any help.

Vehicle: 1985 FJ60
Issue: Previous owner (now decesased) created an electrical puzzle for me to unravel. When purchased the A/C button had to be pushed in for the blinkers to work. I'm not making that up. Looking into this I found the connector at the blower motor was disconnected. When plugged back in the A/C switch didn't have to be pushed in for the blinkers to work. Very strange.

The blower motor does not work in any switch position. The A/C button doesn't light up pressed.

All other electrical items work in the vehicle.

Items checked/corrected so far in this order.
Blower Motor: Hooked directly to 12V for 5 minutes and it ran with no problem. Brushes looked good and I cleaned up everything while I had it out. Checked connector and no voltage.

Fuses: Checked all fuses. None blown and all appear in good condition.

Circuit breaker in dash: Not tripped. Checked continuity of breaker and it is good. No voltage read at location with key turned on.

Fusible Links:
The red wire fusible link was blown. I replaced all three fusible links. All working correctly now.

Circuit breaker in dash: Voltage check now reads 12V with key turned on.

Heater relay: Continuity checked out and it clicks when 12 volts applied. Checked voltage where it plugs in and it is has 12V. When plugged in I do here it click when the key is turned on.

Fan speed switch: No voltage reading at the the switch in any position. I can't reach my hand behind the dash to test where the switch plugs in. To do that I will have to take the entire dash off.

Blower Resistor Switch: Haven't tested and unsure if it is even unplugged. Will check this evening.

Other observations. On the switched side of the starter there is a small (18 gauge) wire that has been cut and is hanging there. Unsure where it is supposed to go. There doesn't appear to have been any auxiliary lights, cb radio or other items installed on this truck at any point. Can't confirm that though.
I do see what appears to be a ground wire that would connect at the windshield wiper motor that is disconnected.

It does appear that another stereo was put in the truck because I can see wire nuts when I look up behind the dash with a flashlight. There is also cheap speaker wire run to each door. The stock radio that put back into the dash and lights up and appears to operate but no sound because the radio antenna wasn't re-installed after the truck was painted. The repaint occurred and then the PO brought it home and passed away.

Current thoughts: I have no idea about the blower motor being unplugged or the AC button needing to be depressed in order for the blinkers. My guess is doing these things helped completed a circuit that allowed the blinkers to work.


So, I have purchased a nice looking cruiser with an electrical puzzle. It really sucks having to rip into this thing but I can get over that if I know everything will work when complete.

I guess it is best for me to pull off the dash, tone all the wiring out, clean everything and install a new radio while everything is torn apart.

PLEASE tell me if you think I'm on the wrong path to track down this issue. I'm all ears for good advice.

Thanks, Bill D.

 

[1911]

There's no accounting for the stuff that previous owners do. FWIW I think you're on the right track; in the end you're going to have to take all the previous crap out and do it right. Take your time and use the schematics in the FSM. One common denominator in most older Cruisers are the various grounds; they can be tenuous after so many years so pay particular attention to them in every circuit. Good luck with it.

 

[txnight]

Poking around this weekend I have found a wire coming off the switched side of the starter solenoid that has been disconnected. After kicking myself for not checking it initially I started studying the diagrams a little harder.

The heater relay needs power from both the circuit breaker and the ignition power wire. I would think that the ignition wire is working correctly because the other electrical systems work correctly.


The heater relay also supplies power to the A/C switch so that would explain why I'm not getting power to both the A/C button and the fan speed switch. Checking again for power at the circuit breaker gave me a good reading at the circuit breaker it's self checks out for continuity.

With all that said I must my issue must lie between the ignition switch and the relay or the circuit breaker and the relay. Either way I now know which terminal to test for power on the heater relay location.

Those are my confusing thoughts. Hopefully this will help someone else down the road.
Updates to follow as long as my multimeter batter holds out.

Bill D.