PSP Switch Signal Circuit Troubleshooting

Turn the ignition switch ON (II).
Measure voltage between ECM/PCM connector terminals A24 and E16.

Fig 1: Measuring Voltage Between ECM/PCM Connector Terminals A24 & E16
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 1.0 V?
1. YES - Go to step 3.
2. NO - Go to step 6.
Start the engine.
Turn the steering wheel to the full lock position.
Measure voltage between ECM/PCM connector terminals A24 and E16.
Is there battery voltage?
1. YES - The PSP switch signal is OK.
2. NO - Go to step 13.
Turn the ignition switch OFF.
Disconnect the PSP switch 2P connector.
Turn the ignition switch ON (II).
At the harness side, connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire.

Fig 2: Connecting PSP Switch 2-Pin Connector Terminals No. 1 & No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure voltage between ECM/PCM connector terminals A24 and E16.
Is there less than 1.0 V?
1. YES - Replace the PSP switch.
2. NO - Go to step 11.
Turn the ignition switch OFF.
Check for continuity between PSP switch 2P connector terminal No. 2 and body ground.

Fig 3: Checking Continuity Between PSP Switch 2-Pin Connector Terminal No. 2 & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair open in the wire between the PSP switch and ECM/PCM (E16).
2. NO - Repair open in the wire between the PSP switch and G301.
Turn the ignition switch OFF.
Disconnect the PSP switch 2P connector.
Turn the ignition switch ON (II).
Measure voltage between ECM/PCM connector terminals A24 and E16.

Fig 4: Measuring Voltage Between ECM/PCM Connector Terminals A24 & E16
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Replace the PSP switch.
2. NO - Go to step 17.
Turn the ignition switch OFF.
Disconnect ECM/PCM connector E (31P).
Check for continuity between body ground and ECM/PCM connector terminal E16.

Fig 5: Checking Continuity Between Body Ground & ECM/PCM Connector Terminal E16
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair short in the wire between ECM/PCM (E16) and the PSP switch.
2. NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck (see ECM/PCM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.