GMT800 No AC with SD only and high volt alternator
2005 GMT800 Serial Cycling AC System, P59 ECU
AC compressor runs enough to pull down to 65-75 psi on low side then cuts off. Will not stay running unless I jump compressor relay. Only stays on momentarily, AC demand is always there. System runs and starts to cool when relay jumped.
Has about 85-90 psi static pressure at 75 degrees ambient.
Tried jumping low pressure switch, also not issue.
Recently went with NA, speed density only setup, no MAF installed. Also switched to 14v battery and adjustable voltage alternator. Currently set for ~15.1-15.3 volts at idle and 15.7-15.9 volts at rpm. Alternator has no F-Terminal.
Tried running on just battery for a minute, system voltage was 14.4 volts and still same behavior. Sometimes I get a service charging system error and battery light in instrument cluster, but AC compressor behaves same with or without error messages. Also tried changing in system tab f-terminal from 1 to a 0 with same results. Masked the charging system high voltage DTC, same behavior.
Tune and log attached showing AC behavior. See anything would prevent the AC from functioning properly?
So if I hold RPM up to 1200-1500 rpm AC clutch will stay engaged. Tried bumping up idle RPM to 925 - no change.
I tried loading up old and old old tunes from last year and neither works either.
This thing is supposed to be my ride for the power tour and I guess I could live with AC cooling when going down road, but would be nice to have AC at idle.
Was the stall saver tables, they were set to same speed as idle speed, doesn't really say what stall saver does, but since setting tables back to stock, the AC works at idle
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