AC, cooling fan, and blower fan simultaneously shutdown

[JamesH]

I am working on my daughter's '96 SL. The radiator cooling fan, AC, and inside blower fan all work great most of the time. Periodically however, all three units shut down simultaneously while driving as if all power were cut off all at once to all three and a 'service engine' light comes on. Then seemingly at random, all three power up, work great, and the service engine light goes off. Have checked and/or replaced all fuses, diodes, relays, and the resistor under the dash. Replaced blower fan. Replaced dash console AC switch and the blower switch. Tested cooling fan and wiring (as much as can assess). Dealer checked all plus the PCM. All seem fine.

Some possibilities left include intermittent PCM failure without a code, intermittent cooling fan motor failure without a code, a wiring problem have not located yet, etc. Anyone else experienced this total air system shutdown problem before? Thanks!

[JerryHughes]

Haven't experienced that but sounds like you may have a short somewhere. Have you had the codes read yet? If not, have them read for free at Autozone. That's where I'd start but if you take it to Autozone, they won't check for codes unless the SES light is currently lit. But you should still have code errors in the history that will show up. They didn't check for "old" codes at Saturn?

Jerry