AC condenser fan doesn't run

[suminfinit92]

We own a 92 Q45 with about 114K miles, last weekend we tried the AC, it blew cold for about a minuite and them blew warm. I took it to our machanic to check it out and he found the condenser fan wasn't running. Where would I start to trouble shoot this problem. I've checked the fuses and reseated the relays. Any ideas? Thanks

[Q45tech]

Check the temperature and pressure switches that drive the relay and check the fan motor by jumping out the relay [pull relay and jump contacts in socket].................usually when the motor fails by jamming it blows the fuse.

The evap fan really only helps at idle as the engine fan pulls way more air above 1500 rpm.

[ardvarkus]

You need the schematic to trouble shoot it.

Figure out what should turn it on, then why it isn't working- either a relay or switch is bad, or the motor is fried. As Q45tech mentioned, jumper the CORRECT contacts and the fan should work- if it doesn't, replace it!

I don't have the 92 schematic- look in the back of the service manual

A

[suminfinit92]

Thanks for the advice, I've jumped the contacts for the fan and it worked fine. Now, how do you troublesoot the relay? And if the relay is good, what trips the relay to power up the fan. If there is a sensorof some kind and where would I find it? Thanks in advance for the help.

[Q45tech]

On the 90-93 there are sensors on the output side of radiator and on the receiver dryer of AC system.....4 sensors to create 3 different aux fan speeds page HA 80 in FSM.

[suminfinit92]

Thanks, unforturnately I don't own an FSN manual. Where could I find a FSM for a 92 Q?

[DAEDALUS]

There are a few manuals on ebay right now for 1st gens. Anything '90-'93 will be a lot of help. Make sure they're factory hardcopy service manuals (not owner's manuals or on CD.)

[Q45tech]

I should have been clearer the 90 had a single speed fan and the 92 has 3 speed fan so try to find the FSM that applies to 92 Q.

Otherwise the wiring and diagrams and sensors will be different.

In the mean time you could run a wire from relay into passenger compartment and manually turn the fan on with a switch. Use the relay as the fam motor draws a lot of current.

[suminfinit92]

Thanks again for all the advice guys, I've went to ebay and checked out the FSM's on ebay and will take advantage. Thanks again.