993 heater blower - won't switch off
Discussion
Have an odd problem with my pre-vario 993.
Took it for a spin this morning and since I got back the heater blower in the engine bay won't stop running even though the ignition is switched off. I've had to unplug the blower to stop it running the battery down. I waited for the car to cool down and then tried to reconnect the blower but it still getting live power so I've had to leave it disconnected.
Any ideas why this blower fan keeps running even though the ignition is off and the key out?
I'm wondering if there is a sender on the engine that thinks it's still hot.
Does the heater blower draw heat away from the engine when the car is parked?
Took it for a spin this morning and since I got back the heater blower in the engine bay won't stop running even though the ignition is switched off. I've had to unplug the blower to stop it running the battery down. I waited for the car to cool down and then tried to reconnect the blower but it still getting live power so I've had to leave it disconnected.
Any ideas why this blower fan keeps running even though the ignition is off and the key out?
I'm wondering if there is a sender on the engine that thinks it's still hot.
Does the heater blower draw heat away from the engine when the car is parked?
I had this on my 993 also. The blower went crazy coming on at various speeds with the ign on or off.
The fix for mine was to replace both the resistor which is plugged in to the side of the air tube and the temp switch which is plugged in to the front of that same air tube. These are common fails and should be replaced together. Cost around £20-25 a piece.
Part Number for Temp Switch is 964.659.120.00
Part Number for Resistor is 964.616.550.02
Others who have had this issue have replaced the relay, so you may want to try this first. They live in the relay box in the engine bay. There should be another in there or up front you can borrow for testing.
The fix for mine was to replace both the resistor which is plugged in to the side of the air tube and the temp switch which is plugged in to the front of that same air tube. These are common fails and should be replaced together. Cost around £20-25 a piece.
Part Number for Temp Switch is 964.659.120.00
Part Number for Resistor is 964.616.550.02
Others who have had this issue have replaced the relay, so you may want to try this first. They live in the relay box in the engine bay. There should be another in there or up front you can borrow for testing.
Thanks Dom. it turned out to be the relay (I think).
I took the cover off the fuse box in the engine compartment, gave the relay a couple of taps and the fan turned off so I think the relay was stuck in the on position. I really need to take it for a spin now and see if the blower still works once the engine is up to running temp - or whether it's just gone off because I've broken the relay.
Is the resistor the coily wire think that is fitted into the slot shaped hole in the plastic tube?
Have you got any good tips on the problem with my oil cooler blower under the right wing. That comes on as soon as I turn the ignition on - even with a cold engine. I've checked the relay for this and it's fine - I tested it by switching it with the relay for the A/C blower. So I'm guessing there must be a temp sender for the oil cooler fan that's faulty?
Cheers
Marc
I took the cover off the fuse box in the engine compartment, gave the relay a couple of taps and the fan turned off so I think the relay was stuck in the on position. I really need to take it for a spin now and see if the blower still works once the engine is up to running temp - or whether it's just gone off because I've broken the relay.
Is the resistor the coily wire think that is fitted into the slot shaped hole in the plastic tube?
Have you got any good tips on the problem with my oil cooler blower under the right wing. That comes on as soon as I turn the ignition on - even with a cold engine. I've checked the relay for this and it's fine - I tested it by switching it with the relay for the A/C blower. So I'm guessing there must be a temp sender for the oil cooler fan that's faulty?
Cheers
Marc
Glad to help.
The Resistor is the coil in the pipe yes. These can go crusty and catch fire apparently!
I had to change the oil cooler and A/C ballast resistors too. Symptoms for those was that they didn't work on low speed. Just kept jumping in at full speed.
Sounds like your one could be a temp probe though.
You can test if the resistors work by doing the following:
Pull the relay and bridge the terminals
For relay R04 - Oil: Connect 3 (30) to 7 (87c) and slow fan speed should operate. 3 (30) to 5 (87) and Fast fan speed will operate.
For relay R14 - AC - As above.
If no slow speed then the Resistors are goosed.
The Resistor is the coil in the pipe yes. These can go crusty and catch fire apparently!
I had to change the oil cooler and A/C ballast resistors too. Symptoms for those was that they didn't work on low speed. Just kept jumping in at full speed.
Sounds like your one could be a temp probe though.
You can test if the resistors work by doing the following:
Pull the relay and bridge the terminals
For relay R04 - Oil: Connect 3 (30) to 7 (87c) and slow fan speed should operate. 3 (30) to 5 (87) and Fast fan speed will operate.
For relay R14 - AC - As above.
If no slow speed then the Resistors are goosed.
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