Switch To Ground

WARNING: This page is about a different variant/trim than selected.

NOTE: Enter this test only when directed here by SWITCH MONITOR TEST. This test is intended to diagnose following switches and circuits: A/C Switch (ACS), Blower Motor Switch (BLMT), Clutch Cycling Pressure Switch (CCPS), Clutch Pedal Position (CPP) Switch, High Pressure Switch (HPS), Idle Switch (IDL), Park/Neutral Position Switch (PNP), Power Steering Pressure Switch (PSP), Rear Defroster Switch (DEF) and Wide Open Throttle Switch (WOT).

CIRCUIT PIN IDENTIFICATION

Circuit	Breakout Box Pin No.	PCM Pin	Wire Color
BLMT	22	1P	Orange/Black
CCPS	41	1O	Pink/Black
HPS	9	2H	Pink/Yellow
IDL	18	1T	Brown
CPP/PNP	30	1R	Light Green/Black
PSP	24	1N	Blue/Yellow
DEF	34	1J	Purple

1) Check System Integrity Visually check all wiring, connectors and components for damage, shorting or looseness. If a fault is found, repair as necessary. If no fault is found, go to next step.

NOTE: If testing Idle Switch (IDL), ensure TPS is properly adjusted. See THROTTLE POSITION (TP) SENSOR in ADJUSTMENTS - 2.5L article.

2) Check Switch Signal To PCM Install breakout box. Connect PCM to breakout box. Measure voltage between ground and appropriate breakout box test pin of switch being tested. Check voltage with switch in open and closed positions. See SWITCH PERFORMANCE CHECK. Voltage should switch from less than one volt (switch closed) to more than 10 volts (switch open). If voltage is not as specified, go to next step. If voltage is as specified, switch is intermittent. See the TESTS W/O CODES - EEC (2.5L) article.

NOTE: For switch connector terminals, see Figure - Figure.

3) Check For Open Switch Wire Ensure ignition is off. With breakout box installed, disconnect PCM connectors. Disconnect switch to be tested. Measure resistance between breakout box test pin of switch being tested and corresponding terminal at switch connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in wire tested.

4) Check For Short In Switch Wire Ensure ignition is off, breakout box is installed and PCM is disconnected. Disconnect switch to be tested. Measure resistance between ground and breakout box test pin of switch being tested. If resistance is less than 10,000 ohms, repair short to ground in wire between switch and PCM. If testing PSP or IDL switch, if resistance is 10,000 ohms or more, replace switch. On all other switches, if resistance is 10,000 ohms or more, go to next step.

NOTE: For switch connector terminals, see Figure - Figure.

5) Check Ground At Suspect Switch Turn ignition off. Disconnect switch to be tested. Measure resistance between ground and GND terminal at connector of switch being tested (if applicable). If resistance is less than 5 ohms, replace switch. If resistance is at least 5 ohms, repair open in ground wire.