N: TEMPERATURE DISPLAY WON'T SWITCH BETWEEN 'C' AND 'F'

PINPOINT TEST N: TEMPERATURE DISPLAY WON'T SWITCH BETWEEN CELSIUS AND FAHRENHEIT

N1 CHECK EATC °F TO °C DISPLAY

- With EATC system on, depress MAX A/C and defrost buttons simultaneously for at least 3/4 of a second.

- Did display switch from °F to °C?

Yes
Go to N2.

- No
Replace EATC control assembly. Restore vehicle. Retest system.

N2 CHECK CIRCUIT 506(R) FOR OPEN

CAUTION: Accidental shorting of the wrong pin could destroy the control assembly.

- With ignition switch in the OFF position, partially remove EATC module as outlined.
- Using a jumper wire connected to a known good ground, connect other end to Circuit 506 (R), Pin 20 at module connector.
- Turn ignition switch to the RUN position.

- Did display change?

- Yes
Go to N3.

- No
Service Circuit 506 (R) for open. Replace damaged EATC module. Restore vehicle. Retest system.

N3 CHECK CIRCUIT 506(R) FOR SHORT

CAUTION: Accidental shorting of the wrong pin could destroy the control assembly.

- Leave jumper connected.
- Using an ohmmeter connected to a known good ground, connect other end to Circuit 506 (R) at EATC module connector Pin 20.
- Measure resistance.

- Is resistance 5 ohms or less?

- Yes
Service Circuit 506 (R) for short. Restore vehicle. Retest system.

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