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Discussion Starter #1
Not the worst thing during the winter but #5 also controls the defroster as well as the reverse lights.

Does anyone have any idea of where i should start looking for the problem, and yes i have searched.

Thanks,

troy
 

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Heater stuck on is a function of the mono valve. the diaphragm is probably torn. It fails in the full on position.
Easy 5 minute change of that. New insert about $70.00.
Mono valve is the square topped assy to the right of the battery with 4 screws and a round bit sticking through the square plate. Unscrew the 4 screws and the assy pulls out. Take note of how assy comes apart so you can reassemble the same way. discard old assy and replace with new assy and the heater should shut off. You will know if the diaphragm is torn when you see it.

Fuse 5 controls the Aux Water Pump near the mono valve if it is toast it'll blow that fuse. Disconnect the electrical plug from the Aux water pump, replace the fuse and see if it blows. If not, your AWP is toast.
Another check is to jump the pins of the AWP from the battery, (one hot, one ground). If it does not come on it is fried and it could (don't remember exactly when the ACC unit and wiring was changed to keep the Aux Water pump from frying the ACC unit), ruin the Acc controls.

Hope this helps.
 

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How fast does the fuse blow when it is replaced.

#5 = 8amp fuse and contains the following accessories:

Back up lamps
Heating water valves
Auxiliary water pump
Climate control system
relay auxiliary fan term,86
Auto trans electrics
Blower motor inside temp sensor
AC compressor
electromagnetic clutch/valve air injection

Do you have a digital volt meter?
I would suspect one of the following to be the cause: climate control unit, auxiliary water pump or the mono valve but that's just my opinion. You need to multimeter to start with.
 

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Discussion Starter #5
Thanks for the reply's, it seems to blow when the heater is turned on though when i pull the klima relay the heat will function properly without blowing which is how im going to leave it for now, though i will check out the mono valve.
 

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Bad Klima Module? Check to see if the Aux water pump is working first.

Thanks for the hint, I didn't know the heater would work with the Klima Module out... I'm having heater problems too, but no blown fuses, just no worky.
Blower motor works if jumped, but Acc don't do much. I'll pull the Klima and see if anything works? I'll report back.

Hmmmmm! Simply Hmmmmm!

Update.
Pulled Klima and nothing happened differently in my car. I did find that the Blower Motor fuse (there was a fuse #16 in the fuse box for the BM until MY1987?), had gotten really hot at one time and melted the plastic around the bottom socket. Cleaned that out too and still no joy. Now I wonder if my Klima module is bad or the regulator, or the ACC??? but still no blown fuzes.
 

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Discussion Starter #7
Im going to check the mono valve in morning since its dark here, though i forgot to mention that i replaced the 8amp white fuse with a blue 25 amp so that may have changed things
 

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Just replaced my mono valve per the intructions mentioned in this thread. My symptoms was that the heater was stuck on in the full heat mode. Now with the new replacement part, I am back to normal.
 

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Upping the amps on a fuse

i replaced the 8amp white fuse with a blue 25 amp so that may have changed things
Generally that's not a good idea. I'd stick to the required strength and search for the cause.
It's easy to start an electrical fire or just melt a lot of stuff , either of which is expensive.
 
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