Heater woes
#1
Instructor
Thread Starter
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Hi All,
Have a1990 C4 Cab. Basically bullet proof in overall terms apart from the usual wear and tear things - but recently noticed that the heater isn't quite working right. As long as I have the A/C on and the temp at low (blue dot) I can adjust the fan speed without any problems and it works fine. If I move the temperature adjustment off the blue dot the fan speed doesn't change at all with any change in the 1-4 selector ****.
Not sure if this is a problem with the temperature selection **** or whether there is some relay somewhere somewhere that I should be checking first.
Keen on any advice.
Mark
Have a1990 C4 Cab. Basically bullet proof in overall terms apart from the usual wear and tear things - but recently noticed that the heater isn't quite working right. As long as I have the A/C on and the temp at low (blue dot) I can adjust the fan speed without any problems and it works fine. If I move the temperature adjustment off the blue dot the fan speed doesn't change at all with any change in the 1-4 selector ****.
Not sure if this is a problem with the temperature selection **** or whether there is some relay somewhere somewhere that I should be checking first.
Keen on any advice.
Mark
#2
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi All,
Have a1990 C4 Cab. Basically bullet proof in overall terms apart from the usual wear and tear things - but recently noticed that the heater isn't quite working right. As long as I have the A/C on and the temp at low (blue dot) I can adjust the fan speed without any problems and it works fine. If I move the temperature adjustment off the blue dot the fan speed doesn't change at all with any change in the 1-4 selector ****.
Not sure if this is a problem with the temperature selection **** or whether there is some relay somewhere somewhere that I should be checking first.
Keen on any advice.
Mark
Have a1990 C4 Cab. Basically bullet proof in overall terms apart from the usual wear and tear things - but recently noticed that the heater isn't quite working right. As long as I have the A/C on and the temp at low (blue dot) I can adjust the fan speed without any problems and it works fine. If I move the temperature adjustment off the blue dot the fan speed doesn't change at all with any change in the 1-4 selector ****.
Not sure if this is a problem with the temperature selection **** or whether there is some relay somewhere somewhere that I should be checking first.
Keen on any advice.
Mark
Sounds like your rear blower (engine compartment is non functioning), there's lots of info on this topic when you search the forum. This thread is a good start
https://rennlist.com/forums/964-foru...ml#post7147678
Rgds,
Harald
#3
Three Wheelin'
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Whilst I concur with Harald about the rear blower, my concern is that where the rear blower fails to start the cabin blowers would normally stop completely after a second or two regardless of the state of the speed switch. It might suggest there is another problem. Make sure the rear blower fuse is a 30 amp part too!!
Regards
Dave
Regards
Dave