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Home >> Infiniti >> 1999 >> G20 L4-2.0L (SR20DE) >> Repair and Diagnosis >> Heating and Air Conditioning >> Control Module HVAC >> Testing and Inspection >> A/C Control Unit Check
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A/C Control Unit Check







Check power supply circuit for auto amp. with ignition switch ON.
Measure voltage across terminal Nos. 26, 27, 33 and body ground.







Check body ground circuit for auto amp. with ignition switch OFF. Check for continuity between terminal Nos. 32, 14 and body ground.
If OK, check auto amp. ground circuit, see below.
- If NG, check 7.5A fuse (No.5), 10A fuse (No.8) (located in the fuse block) and 15A fuses (No.1 and 2, located in the fuse block).
- If fuses are OK, check for open circuit in wiring harness. Repair or replace as necessary.
- If fuses are NG, replace fuse and check wiring harness for short circuit. Repair or replace as necessary.

NOTE: If OK, replace auto amp. If NG, repair or replace harness.
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