AC/Blower issue.

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ilouie
Posts: 13
Joined: Mon Oct 16, 2017 8:50 pm
Location: Miami

AC/Blower issue.

Post by ilouie »

Hi, I was wondering if someone has seen this issue. The Blower Motor only works on high, which is due to the Transistor. My problem is that when I turn the AC on (Push Switch in), the Blower stops working. Would that be because of the bad Transistor?. Thanks in advance.
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Brucey
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Re: AC/Blower issue.

Post by Brucey »

no, that is perfectly normal. The normal blower is disabled when the AC is on, there is (meant to be) a separate blower when the AC is on.

If the main blower only works on full, the fault can either be the big transistor, bolted in the blower housing, which is readily accessible, or the small transistor/circuit board in the dash module, which is not at all readily accessible.

So my advice is to lubricate the motor bushings (but to avoid contamination of the motor brushes) until the blower spins very freely, then to check/replace the big transistor, and if that does not work then and only then venture into the dashboard to rebuild/replace the blower control circuitry.

If the AC blower does not work, there could be a similar fault-finding routine for that also.

NB the AC blower uses an output from the same control module as the main blower. Certain faults with the AC blower may cause the control circuitry to fry itself. So you could carry out a long and boring repair of the control module only to cause it to fail again if the AC blower circuitry is also faulty. BTW there is no override (full speed) setting for the AC blower; it only works via the control module and its own power transistor, I think.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ilouie
Posts: 13
Joined: Mon Oct 16, 2017 8:50 pm
Location: Miami

Re: AC/Blower issue.

Post by ilouie »

Thank you Brucey. I've found out that the problem is with the AC Blower under the dash/console. I took it out and put it directly to the battery but it doesn't move. also, can I replace the AC Blower motor with the Main Blower motor?. I live in Florida and we don't use the heat. Thanks.
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Brucey
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Re: AC/Blower issue.

Post by Brucey »

ilouie wrote: Tue Oct 24, 2017 5:18 pm also, can I replace the AC Blower motor with the Main Blower motor?.
no I don't think so... It is quite different, isn't it?

you need the main blower motor for demisting the windscreen and blowing fresh air into the car. Not sensible (or safe) without it, I'd say.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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