Diagnostic Aids

Perform this test only when directed by QUICK TEST. This test is intended to diagnose following.

Clutch Pedal Position (CPP) switch
Park/Neutral Position (PNP) switch
Powertrain Control Module (PCM)
Wiring harness circuits (CPP, PNP and SIG RTN)

Fig 1: PNP Switch Circuit Schematic (TA1 - All Models With A/T)

Fig 2: CPP Switch Circuit Schematic (TA2 - B2300 & B3000 With M/T)

TEST PIN NO. 30 (CPP/PNP) WIRE COLOR IDENTIFICATION

Application	Wire Color
B2300 & B3000	Light Blue/Yellow

TEST PIN NO. 46 (SIG RTN) WIRE COLOR IDENTIFICATION

Application	Wire Color
B2300 & B3000	Gray/Red

1) Code 522, 525 Or 528 Code 522, 525 or 528 is a result of voltage being high at either pin No. 10 (A/C input) or No. 30 (CPP/PNP input) while cranking engine or during KOEO SELF-TEST. Following are possible causes of faults.

A/C circuit shorted to power
CPP or PNP circuit open
Faulty Powertrain Control Module (PCM)
Starter relay disconnected during self-test

On all A/T models, go to step 8). On all M/T models, go to next step.

2) Check CPP/PNP Input Turn ignition off. Turn A/C off (if equipped). Disconnect 60-pin PCM connector. Inspect terminals and repair if damaged. Install EEC-IV Breakout Box (T83L-50-EEC-IV), leaving PCM disconnected. Measure resistance between test pins No. 30 and 46 with transmission in Neutral and clutch pedal up. Measure resistance between test pins No. 30 and 46 with transmission in gear and clutch pedal down. If each resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 5).

3) Check CPP/PNP Switch Integrity Leave ignition off and PCM disconnected. Measure resistance between test pins No. 30 and 46 with transmission in any gear and clutch pedal up. See Fig 3. If resistance is less than 5 ohms, go to CIRCUIT TEST KM, step 40) (models with A/C) or replace PCM and repeat QUICK TEST (models without A/C). If resistance is 5 ohms or more, go to next step.

Fig 3: Neutral Gear/Clutch Input Circuit (TA4 - B2300 & B3000)

4) Check For CPP Short To Ground Leave ignition off and PCM disconnected. Disconnect CPP switch. Measure resistance between test pins No. 30 and 46. If resistance is 10,000 ohms or more, go to CIRCUIT TEST KM, step 40) (models with A/C), or replace PCM and repeat QUICK TEST (all others). If resistance is less than 10,000 ohms, repair short circuit. Reconnect all components, and repeat QUICK TEST.

5) Check CPP/PNP Switch Leave ignition off and PCM disconnected. Locate PNP switch (on transmission) and CPP switch (at clutch pedal linkage). Disconnect wiring harness at both switches. Measure resistance across PNP switch terminals with transmission in Neutral. Measure resistance across CPP switch with clutch pedal down. If each resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, replace switch and repeat QUICK TEST.

6) Check CPP/PNP Wiring Harness Leave ignition off and PCM disconnected. Measure resistance between test pin No. 30 and following terminals.

PNP switch wiring harness connector CPP and/or PNP terminal
CPP switch wiring harness connector CPP and/or PNP terminal

Measure resistance between test pin No. 46 and following terminals.

PNP switch wiring harness connector SIG RTN terminal
CPP switch wiring harness connector SIG RTN terminal

If any resistance is 5 ohms or more, repair open circuit and repeat QUICK TEST. If each resistance is less than 5 ohms, go to CIRCUIT TEST KM, step 40) (models with A/C), or replace PCM and repeat QUICK TEST (models without A/C).

7) Check CPP Switch Turn ignition and A/C off. Disconnect 60-pin PCM connector. Inspect terminals and repair if damaged. Install EEC-IV Breakout Box (T83L-50-EEC-IV), leaving PCM disconnected. Push clutch pedal down. Measure resistance between test pins No. 30 and 46 at breakout box. If resistance is less than 5 ohms, go to CIRCUIT TEST KM, step 40) (models with A/C) or replace PCM and repeat QUICK TEST (models without A/C). If each resistance is 5 ohms or more, repair open circuit. Reconnect all components, and repeat QUICK TEST.

8) Check PNP Input Turn ignition and A/C off. Disconnect 60-pin PCM connector. Inspect terminals and repair if damaged. Install EEC-IV Breakout Box (T83L-50-EEC-IV). Connect PCM to breakout box. Ensure transmission is in Neutral or Park. Turn ignition on. Measure voltage between test pin No. 30 and chassis ground. If voltage is less than one volt, go to CIRCUIT TEST KM, step 40) (models with A/C), or replace PCM and repeat QUICK TEST (models without A/C). If voltage is one volt or more, go to next step.

9) Check PNP Switch Resistance Turn ignition off. Disconnect PCM from breakout box. Disconnect PNP wiring harness connector. Measure resistance across switch terminals. If resistance is less than 5 ohms, repair open in PNP circuit and repeat QUICK TEST. If resistance is 5 ohms or more, replace PNP switch and repeat QUICK TEST.