ECU involvement in A/C?
stenseltizm
07-29-2004, 02:29 PM
I'm taking a 2.8V6 out of my Camaro, and installing a Carb'ed 400 sb. I already did the mounts, tranny, fuel, coolant etc. etc. But I want all my factory options to work. I rewired my gauges, Dist., cooling fan etc. But I heard that the ecu also controls the A/C comp. instead of just a mechanical relay. Is this true, or just it just taking a reading so that it can adjust rpm's etc. I figured out the ps shutoff, the cooling fan link, and the High Pressure emergency shut off. The schematic shows another switch as a cycling switch. Is this what acually control the comp, or just a saftey for the ecu. I have most of the spagetti under control, but every time I think I have this one figured out, I hear something else.
Thanks in advance
Thanks in advance
stenseltizm
07-29-2004, 02:30 PM
Basically I want to remove the ecu, without blowing anything up.
tom3
07-29-2004, 05:26 PM
I think the computer gets an AC request, but doesn't actually control the compressor or fans. On a late 80s Camaro you have a low pressure cutoff at the dryer, high pressure fan switch just above the pass. side frame on the smaller high pressure line, a high pressure cutout on the back of the compressor, and that's about it. Pretty simple system back then.
stenseltizm
07-29-2004, 06:06 PM
The schematic shows the a/c selenoid controling loop going through the ecu. does the non fuel injected model not have the selenoid at all?
stenseltizm
07-30-2004, 09:22 AM
I think I figured it out. The relay is looped through the ecu. The signal tells the ecu to increase idle speed, and the relay allows the ecu to temporarily shut down the compressor when the engine needs the horse power. Many cars don't even have that relay.
Thanks
Thanks
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