Are cooling fans using to much electricity?

[Srmichi23]

i got a 94 lumina with around 24k miles on it. trying to figure out why my car turns off or tries to turn off on me when i turn ac on. i notice when i turn the ac the cooling fans turn on and sometimes my car would turn off. well i think only when the second fan turns on it happens ( isn't the second one that turns on with the ac?) for example i drove my car without ac picked up a person and i turn on ac and i guess the second fan turns on and the car dies. or I'm driving in the highway and since the fans don't turn on if you going faster than 35mph when i come to a stop the fans kick in and the car dies.

i did change the compressor and accumulator and filter before this started to happen. but i don't really know if it did this before i changed the parts I bought the car with the compressor shot.

[jeffcoslacker]

The secondary fan comes on whenever the compressor cycles on.

Most times when they act like yours, either there is a problem with extreme high side pressures in the A/C system from overcharging or blockage, the alternator/regulator isn't stepping up fast enough to keep up with the sudden demand from A/C comp and fans turning on, the battery could be in marginal condition (will sometimes cause the voltage regulator to act erratic) or the car may not stepping up idle speed to meet the demand.

I'd check high side pressure first, then charging voltage when the system turns on. See if it's dying from load, lack of electrical power, or idle speed.

[jeffcoslacker]

I see in another thread you seem to be thinking your battery is bad...I bet this is your problem if so...

I had one going bad over the winter...I first noticed the headlights surging when I used the turn signals, and dimming momentariyl when I stepped on the brake or turned on defrost, etc...then sometimes when I put it in gear it would stumble and almost die...

I was a bit aggravated because I just put an alternator on it a year ago, and thought it was going out. I checked it with a good tester, which actually indicated a bad diode in the alternator, which was what I expected based on what I was seeing...but being methodical, I tested the battery too, and turns out it was barely alive, even though still starting the car well enough...but after a 15 second load test it couldn't even engage the starter solenoid....

New battery, and all is fine now.

[Srmichi23]

thanks for the reply Jeff. i forgot to mention that i replace the alternator like a month ago or so and i remember that when i bought the car the previous owner had giving me a receipt for a new ac delco battery they bought. well i found the receipt and they had purchase it 09/13/07. so i guess I'm leaning more with extreme high side pressures in the A/C system from overcharging or blockage. how would i go about checking this out? what should the High side pressure be? What should the low side be? I check it while the system is on right? I'm going to try to get pressure tester later today and see what the outcome is.

also i do know they barley drove the car do you think the battery went bad from sitting there for 4 months or so during the winter?

[Srmichi23]

well i went to see if i could check the pressure but my friend did not have the right fitting for the high side. he will try tomorrow to get one for me at his job.