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G: SYSTEM DOES NOT CONTROL TEMPERATURE

PINPOINT TEST G: SYSTEM DOES NOT CONTROL TEMPERATURE

G1 PERFORM EATC SELF TEST

- Turn the ignition switch to RUN.
- Press OFF and FLOOR buttons simultaneously and then press AUTOMATIC button within two seconds.
- Self test may run as long as 30 seconds.
- After self test, record all error codes and any temperature display readings.
- Press the blue (Cooler) button to exit self test.

- Is error code 030, 031, 032, or 033 displayed?

- Yes
Go to G2.

- No
Go to G3.

G2 CHECK SENSOR RESISTANCE

NOTE: An open sensor will cause the warm air discharge at 65°F (18°C) setting. A shorted sensor will cause cool discharge air at 85°F (29°C) setting.






- Disconnect the A/C ambient air temperature sensor.
- Using a DVOM, measure the resistance across the sensor terminals and compare the readings with the sensor resistance table.

- Are resistance values within the specified limits?

- Yes
Go to G3.

- No
Replace A/C ambient air temperature sensor and bracket. Restore vehicle. Retest system.

G3 CHECK ASPIRATOR INSTALLATION

- Gain access to automatic temperature control sensor hose and elbow as outlined.
- Check for proper installation of automatic temperature control sensor hose and elbow.

- Is aspirator installed properly and hose connected?

- Yes
Go to G4.

- No
Service automatic temperature control sensor hose and elbow as necessary. Restore vehicle. Retest system.

G4 CHECK AUTOMATIC TEMPERATURE CONTROL SENSOR OUTPUT AT EATC MODULE

- Turn engine off. Leave ignition switch in RUN position.
- Disconnect automatic temperature control sensor.
- Using a voltmeter, check Circuit 790 (W/O) at Pin 17 of connector C1 for voltage.

- Is voltage present?

- Yes
GO to G5.

- No
Replace EATC module. Restore vehicle. Retest system.

G5 CHECK AUTOMATIC TEMPERATURE CONTROL CIRCUIT 790 (W/O)

- Turn ignition switch OFF.
- Using an ohmmeter, check Circuit 790 (W/O) from EATC module to automatic temperature control sensor connector.

- Is there continuity?

- Yes
Go to G6.

- No
Service Circuit 790 (W/O) for open. Restore vehicle. Retest system.

G6 CHECK AUTOMATIC TEMPERATURE CONTROL SENSOR RETURN CIRCUIT

- Using an ohmmeter, check Circuit 470 (PK/BK) for continuity from EATC module to aspirator connector.

- Is there continuity?

- Yes
Replace automatic temperature control sensor. Restore vehicle. Retest system.

- No
Service Circuit 470 (PK/BK) for open. Restore vehicle. Retest system.