
AC–70
AIR CONDITIONING SYSTEM – TROUBLESHOOTING
INSPECTION PROCEDURE
1 Check voltage of TSET terminal on A/C amplifier.
ON
Connect
TSET
SG
BE3840
N08961
P Remove A/C amplifier with connectors still connected.
C 1. Turn temperature set dial.
2. Check voltage between terminals TSET and SG of A/C amplifier.
OK
Set Temperature Voltage
20°C (68°F) 3.88 V
25°C (77°F) 2.50 V
30°C (86°F) 1.12 V
NG
OK Proceed to next circuit inspection shown on matrix chart (See page AC–26).
2 Check voltage of terminal on A/C control assembly.
H12-2
(TSET)
H12-11 H12-10 H12-9
(SG) (S5) (GND)
N08834
P Remove A/C control assembly with connectors still connected.
C Check voltage between following terminal and H12–9 (GND) of A/C control assembly connectors.
OK
Check Terminals Voltage
H12-10 ⊕ – ⊖ H12-9 4.5 – 5.5 V
H12-11 ⊕ – ⊖ H12-9 Below 1.0 V
H12-2 ⊕ – ⊖ H12-9 See procedure 1.
NG
OK Repair or replace harness or connectors between A/C amplifier and A/C control assembly.
3 Check harness and connectors for S5 and SG signal.
OK
NG Repair or replace harness or connectors between A/C amplifier and A/C control assembly.
Replace A/C control assembly.