Inspection Procedure

DTC 51 - Switch Condition Signal

INSPECTION PROCEDURE
1. Check output condition of diagnostic trouble code 51.
- Setting the test mode.
a. Turn ignition switch OFF.
b. Connect terminals TE2 and E1 of data link connector 1.
c. Turn ignition switch ON.
(For checking terminal IDL, disconnect the vacuum hose from the throttle body, then apply vacuum to the throttle opener)
(For checking terminal A/C, start the engine)
d. Connect terminals TE1 and E1 of data link connector 1.




- Check if code "51" is output by the Malfunction Indicator Lamp.

Switch Condition Signal - Test Mode Results:

HINT: Diagnostic trouble code 42 is output with vehicle speed 3 mph (5 km/h) or below.
- If OK proceed to next circuit on the diagnostic matrix chart under Diagnosis by Symptom.
- If not OK:
- PNP signal - go to Park/Neutral Position Switch Diagnostic Chart.
- A/C signal - proceed to step 3.
- IDL signal - proceed to step 2.

2. Check resistance of throttle position sensor.
a. Disconnect throttle position sensor connector.
b. Disconnect the vacuum hose from the throttle body, then apply vacuum to the throttle opener.




c. Measure resistance between terminals 2 (IDL) and 1 (E2) of throttle position sensor connector.

Throttle Valve - Resistance
Closed - less than 2.3 k Ohms
Opened - 1 M Ohm or higher
- If OK check and repair harness or connector between engine control module and throttle position sensor.
- If not OK adjust or replace throttle position sensor.

3. Disconnect A/C amplifier connector, check voltage between terminal 2 of A/C amplifier connector and body ground.
a. Remove glove compartment.
b. Disconnect A/C amplifier connector.
c. Turn ignition switch ON.




d. Measure voltage between terminal 2 of A/C amplifier connector and body ground.
Voltage specification: 9 - 14 volts
- If OK proceed to step 4.
- If not OK check and replace A/C amplifier.

4. Check for open and short in harness and connector between engine control module and A/C amplifier.
- If OK check and replace engine control module.
- If not OK repair or replace harness or connector