Help-need advice as ac and ac cooling fan inop - changed temp sensor-changed both relays - comp clutch and ac acooling fan both good - fuses good - belive comp good - could this be my pcm?


started out was service engine light soon - got out by disconnecting battery as car was running well - had a minor water leak due to sunroof seal - I'm stuck any ideas?
Edited by: sw2cam

Is there power going to the fan motor? Could be the motor itself,not unheard of.

Thanks for the feedback as I am going nuts wth this. I wondered about the fan also so following Chiltons I jumped the fan directly to the battery - ran a wire from + of battery and it ran great - also as I didn't have to add a ground it confirmed my ground wire was in tact - so far I have the fan that will run if I jump it, the electric clutch on the compressor that will work if I jump it, following chiltons all the way - also went to under hood fuse box and checked if power was coming from where the relays - 1 for blower, 1 for ac - even changed the relays I hate to think PCM - as I belive it is the boss of the AC and under hood fan system Maybe the fan would come to cool the radiator if the antifreeze got hot enough, do have a fairly new radiator and its pretty cool here right now so not sure. The internal gage never usually gets any higher than 1/4 up-bit also read that there are 2 temp sensors - 1 for the gage and 1 to tell the brain the engine temp to control the fan etc. I'm open for more input and really appreciate it.
Edited by: sw2cam

pcm's rarely go bad. I'd like to see you check for power using both terminals at the fan connector to see if the pcm is commanding it on and the wiring is good. Best way is to turn on the a/c if it is not too cold to come on. If the a/c clutch is not coming on possibly not enough charge in the a/c. If this is the case you could jump the pressure sensor located in the a/c line near the back of the battery.dont quote me on this but I beleive the ground is on the upper trans to block bolt.Let me know what you come up with p/m if you'd like. Jim BY the way did you get a code from the ses light being on? code 26 maybeEdited by: original007

Thanks 007 - I'll check the fan at the plug- did some troubleshooting fo the fan already by bareing wire and connectiong to + side of battery, but now need to check at plug w/ ac on to check pcm -Thanks Clutch does fire if I jump it . I had a code which started this but lost it by disconnecting the battery-stupid, but car was running ok and wife hates the light. when the light came on I had no Idea the ac fan or ac wasn't working.Found the ac pressure switch - kindo fo strange plug on it, so will try and get it off w/o breaking- Thanks a lot for your time - w/a Edited by: sw2cam

Like original007 posted, PCM rarely go bad. Actually they never "go bad". They either work or they dont.

You car doesnt have two temperature sensors. Only OBDI (1991-1995) Saturns have two. OBDII (1996-2002) have only one.

To test if it is the A/C pressure switch, unplug the connector and jumper the two connections.

Ok, so did this LOW SATURN-jumped pins 30 and 87 at radiator fan relay with ign on - fan lit up sounds normal - ok
unplugged rad fan-turned on car and ac - used multimeter and found no juice going to fan - you would think maybe relay bad- but already changed itduring all this - also the ac relay? I pulled the plug on the pressure switch and tried to jump it - maybe I had a mind freeze - check my moi - ground to one side of switch - battery + to other - ( both to the actual switch - no change - so could be stuck closed- oh I turned on ac and found plenty of DC to the plug side - so felt good thet a signal was being sent.
The compressor clutch will take a direct jump.
Any ideas- maybe bad press switch? If so is that a big deal?

If I missed this, I'm sorry. But does the system have pressure?

I checked and without compressor running ( as I can't get it to) - has apx. 25 psi ish. If I have no service engine soon light could I still have a code in the system to help? have thought about buying a code reader.
I just don't think my comepressor is shelled out - it gave no warning or anything and car never overheats - we're in winter here in AZ so car wouldn't but fan mostly came on only when AC was on in the summer.
Again, could it be the pressure switch that is teling the compressor that we have an over pressure condition so don't run?

Are you working using a service manual?

I uploaded the A/C compressor non operation flow chart.

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