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Old 11-23-2015, 07:03 AM   #2
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Join Date: Nov 2006
Location: Out on the Tiles
Posts: 624

1) Do the DRLS themselves work properly, and only the dash indicator is goofy, or do the DRLs behave in sync with the dash light?

2)The AC on/off cycling sounds like a system that is low on charge but just high enough to keep from triggering the low pressure cutout when at rest. When the system is turned on, the low side pressure drops (by design), but if there is not enough refrigertant in the system, the low side pressure will dip below the low pressure cutoff, cutting out the AC clutch. The low side pressure then rises back to where it was at rest, the clutch kicks in, and the cycle repeats over and over in a very regular manner. The leak will, of course, be in one of the components you did not replace.

You could have an issue with the Hi/lo pressure switch, the A/C relay, or just be low on refrigerant--or an outside chance that the request for AC going to the BCM does not end up providing the required signal to trigger the relay to complete the AC circuit. I was going to say the chance was tiny but you have the same BCM in both cases.

As for the A/C not coming on when requested using the button, that again could be caused by low refrigerant, a bad lo/hi pressure switch, or lack of signal from BCM, or defective AC relay.

Technically, shouldn't rule out AC clutch issues either.....could be responsible for the cycling and the no AC condition

Step 1: Read the hi and lo pressure ports at rest and with AC running
Step 2: Get ready with that voltmeter.....
97 SC2 ~253K

95 SC2 ~235K +/running-- "All in the Family"
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