| Author |
Message |
Erik R. K. Jonsson (Gamester)
Member
Username: Gamester
Post Number: 341
Registered: 11-2000
| | Posted on Saturday, June 14, 2003 - 2:56 am: | |
Often they do, but with a Fluke VOM you can set it to diode check, where in this case both outer leads on the transistor were shorted in either direction. I pulled the xstr and retested the circuit and the transistor and only the xstr showed a short. There is a 555 timer in the circuit with the xstr and they rarely fail from my experience. The xstr which shorted is the driver for the xstr inside the dash vent. Most xstrs will show a ~.500 or so on the fluke meter as you move the leads around, and typically only in 2 combinations of the lead hookup. |
billy bob (Fatbillybob)
Member
Username: Fatbillybob
Post Number: 288
Registered: 8-2002
| | Posted on Saturday, June 14, 2003 - 12:14 am: | |
Erik,
How did you diagnose the transister. Don't those things do different things with a VOM when in circuit vs out of circuit and when a capacitor is near them etc?? |
Erik R. K. Jonsson (Gamester)
Member
Username: Gamester
Post Number: 339
Registered: 11-2000
| | Posted on Friday, June 13, 2003 - 7:58 am: | |
Got it fixed. The transistor inside the control unit( under the knob) for the fan speed was shorted. Now once again have full fan control. |
Erik R. K. Jonsson (Gamester)
Member
Username: Gamester
Post Number: 337
Registered: 11-2000
| | Posted on Wednesday, June 11, 2003 - 8:52 pm: | |
Found the post re: how to on the transistor replacement...
http://www.ferrarichat.com/discus/messages/256120/210784.html
Tested the transistor with the fluke meter but it checks ok, may have a problem with the rheostat.
The transistor is accessed on the mondial through the 3 bank of vents dead center. |
Erik R. K. Jonsson (Gamester)
Member
Username: Gamester
Post Number: 336
Registered: 11-2000
| | Posted on Wednesday, June 11, 2003 - 7:08 pm: | |
Found the problem, the 4 pin connector behind the panel in front of the handbrake was disconnected. This cured the rear brake light and the rear window power problem! Likely undone when a nebish removed the alarm. Of course the wiring diagram manual shows only one connector at each end of the wires.
I will search the JRV post, thanks
Erik |
Don Vollum (Donv)
Junior Member
Username: Donv
Post Number: 102
Registered: 1-2002
| | Posted on Wednesday, June 11, 2003 - 12:15 pm: | |
I had some similar problems, and it is my understanding that power for the brake lights goes through the control box for the warning system. Could that be the problem?
In my case, we ended up buying a used control box.
As for the transistor, do a search-- JRV once explained exactly how to change it. And no, it's not all that easy. |
Erik R. K. Jonsson (Gamester)
Member
Username: Gamester
Post Number: 333
Registered: 11-2000
| | Posted on Wednesday, June 11, 2003 - 10:55 am: | |
The 3rd brakelight red wire has power at the connector under passenger footrest, none at the rear bonnet connector. Wiggled the wire all over in the engine compartment but had no intermittent connection.
The rear window lockout blue wire has power with the key on(under the lockout switch on the dash) but the switches in the center console(blue wire) have no +12.
The heater-A/C fan only works fully clockwise(full on high speed) any idea where exactly the transistor which runs this is located and if just the transistor is easily replaced?
Any other tricks would be appreciated! I am thinking of borrowing a broken wire detector from a utility contractor.
Thanks
Erik |