DTC P0550

DTC P0550	PSP switch circuit malfunction
DETECTION CONDITION	The PCM monitors PSP switch signal at PCM terminal 2T. If input voltage is low voltage (switch stays on) for 1 min when the VSS is above 60.0 km/h {37.3 mph} and ECT is above 60°C {140°F} , the PCM determines that PSP switch circuit has malfunction. Diagnostic support note This is a continuous monitor (CCM). The MIL illuminates if the PCM detects above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	PSP switch connector or terminals malfunction PSP switch malfunction Short to ground in wiring harness between PSP switch terminal A and PCM terminal 2T PCM connector or terminals malfunction PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED Has the FREEZE FRAME DATA (Mode 12) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2	VERIFY RELATED SERVICE BULLETINS AVAILABILITY Verify related Service Bulletins availability. Is any related Service Bulletins available?	Yes	Perform the repair or diagnosis according to the available Service Bulletins. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT PSP SWITCH CONNECTOR AND TERMINALS Turn the ignition switch off. Disconnect PSP connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 7.
3		No	Go to the next step.
4	INSPECT PSP SWITCH Inspect the PSP switch. (See POWER STEERING PRESSURE (PSP) SWITCH INSPECTION ). Is there any malfunction?	Yes	Replace the PSP switch, then go to Step 7. (See POWER STEERING OIL PUMP DISASSEMBLY/ASSEMBLY ).
4		No	Go to the next step.
5	INSPECT PSP SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND PSP switch connector is disconnected. Inspect for continuity between PSP switch terminal A (wiring harness-side) and body ground. Is there continuity?	Yes	If the short to ground circuit could be detected: Repair or replace the wiring harness for a possible short to ground. If the short to ground circuit could not be detected: Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION ). Go to Step 7.
5		No	Go to the next step.
6	INSPECT PCM CONNECTOR AND TERMINALS Disconnect PCM connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to the next step.
6		No	Go to the next step.
7	VERIFY TROUBLESHOOTING OF DTC P0550 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. Start the engine. Drive the vehicle above 60.0 km/h {37.3 mph} for 1 min. Verify the at the ECT PID above 60°C {140°F} using the M-MDS. Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
7		No	Go to the next step.
8	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
8		No	DTC troubleshooting completed.