Cheers, I am in Sydney and have imported a Jan 89 Testarossa from the UK (RHD), The variable temperature control has been disconnected and a switch inserted to turn the heater tap either full on or off. (Very hot or cold). The variable speed fan control only works at full speed and when the A/C is engaged. So not for normal airflow. Is this normal? I am removing the Themo Fan at the condenser as it does not work (probably salty). Having owned a 308 for 17 years I am used to the electrics issues with Ferrari but am uncertain whether to just change the switches or if something else needs to be addressed. Have looked for 6 six hours on archives with no success but am new to this site. Any help is appreciated. Paul V
Paul, The fault with the fan speed could be just the switch, however sometimes it's the power transistor (part number 127014), it's mounted on the a/c / heater unit inside the car. In case you need a wiring diagram here it is, the power trasistor is the oval shaped part with the terminal letters C E B on it................. It's also shown in the second picture - item number 14.......
I had my a/c fan speed switch rebuilt recently and it worked for almost a full day before burning out again. The unit would only blow on high speed or it would be off, there was nothing in between. When it was repaired it worked beautifully in all speeds on heat or cold. Now that it is broken again it does not work on any speed. I am completely without a/c or heat or ventilation now. It broke on a 105 degree day after being parked in the sun for about 15 minutes. I think the problem is with an electrical component mounted in the airstream in the dash/center console between the fan speed switch and the HVAC unit. The circulating air is supposed to keep it cool but it over heats and burns itself out. You have to dig pretty deep in the dash to get to that component and it's a pretty expensive part to replace. Several F-Chatters suggested that I just live with the full fan speed or off fan speed as part of Testarossa ownership. I think this is a fairly common problem. I have heard of someone in the Houston, TX chapter installing a small personal computer CPU fan and heat sink next to the failing component to help keep it cool and extend it's life. Good luck with the repair. Let us know if you get it fixed.
Paul V -- Do a search on the key words "power transistor" from Malcolm's post (here and at the old site). Anything below full-speed uses the power transistor and the electronics of the speed control ECU switch, while full-speed uses just a simple on-off switch built into the speed control ECU switch and a relay -- so your report of "only full-speed works" is the usual reported problem with the TR interior fan (and the "added" switch is just functioning in the same manner as the simple switch in the speed control ECU switch would). Your other "mod/fix" to the temp control system is more troubling. IIRC, the temp control knob is just a variable resistor so if that was the problem not sure why it wasn't just replaced (i.e., shouldn't be ridiculous $). IMO, you'd need the relevant AC chapter from the TR WSM to delve deeper on this.
