DTC P1189 [WL-3]

id0102b8956600

DTC P1189

Fuel pump speed sensor circuit malfunction
DETECTION CONDITION
•  The PCM monitors the fuel pump speed sensor signal at PCM terminal 2D and 2K. If the difference between engine speeds detected by the fuel pump speed sensor and the CKP sensor is 500 rpm or more for 1s continuously under the following conditions, the PCM determines that the fuel pump speed sensor circuit has a malfunction.
―  The engine speed detected by the fuel pump speed sensor is lower than that detected by the CKP sensor
―  The engine is running
POSSIBLE CAUSE
•  Fuel pump speed sensor malfunction
•  Poor connection at fuel pump speed sensor or PCM connector
•  Fuel pump speed sensor circuits are shorted each to other.
•  Short to ground circuit between fuel pump speed sensor terminal (Fuel injection pump connector C) A and PCM terminal 2K
•  Short to ground circuit between fuel pump speed sensor terminal (Fuel injection pump connector C) B and PCM terminal 2D
•  Open circuit between fuel pump speed sensor terminal (Fuel injection pump connector C) A and PCM terminal 2K
•  Open circuit between fuel pump speed sensor terminal (Fuel injection pump connector C) B and PCM terminal 2D
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
•  Verify related service repair information availability.
•  Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
2
VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
•  Clear the DTC.
•  Start the engine.
•  Is the same DTC present?
Yes
Go to the next step.
No
Intermittent concern exists.
Perform the “INTERMITTENT CONCERN TROUBLESHOOTING”.
(See INTERMITTENT CONCERN TROUBLESHOOTING [WL-3].)
3
VERIFY FUEL PUMP SPEED SENSOR VOLTAGE
•  Disconnect the fuel pump speed sensor connector.
•  Connect the voltmeter fuel injection pump connector C terminals A and B (part-side).
•  Check the voltage in the AC range while cranking the engine.
•  Is there any voltage reading?
Yes
Go to the step 5.
No
Go to the next step.
4
VERIFY FUEL PUMP SPEED SENSOR
•  Perform the fuel pump speed sensor inspection.
•  Is the fuel pump speed sensor normal?
Yes
Check for poor connection (damaged, pulled-out terminals, corrosion, etc.) or a bent terminal of the fuel pump speed sensor.
•  Repair or replace if necessary, then go to Step 9.
No
Go to the next step.
5
INSPECT PCM CONNECTOR POOR CONNECTION
•  Turn the engine switch to the off position.
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 9.
No
Go to the next step.
6
INSPECT FUEL PUMP SPEED SENSOR CIRCUIT FOR OPEN CIRCUIT
•  Inspect the following terminals for continuity:
―  Between fuel injection pump connector C terminal A and PCM terminal 2K
―  Between fuel injection pump connector C terminal B and PCM terminal 2D
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace open wiring harness, then go to Step 9.
7
INSPECT FUEL PUMP SPEED SENSOR CIRCUIT FOR SHORT TO GROUND
•  Inspect the following terminals for continuity:
―  Between fuel injection pump connector C terminal A and body ground
―  Between fuel injection pump connector C terminal B and body ground
•  Is there continuity?
Yes
Repair or replace wiring harness, then go to Step 9.
No
Go to the next step.
8
INSPECT FUEL PUMP SPEED SENSOR CIRCUIT FOR SHORT TO EACH OTHER
•  Check for continuity between fuel injection pump connector C terminals A and B (wiring harness-side).
•  Is there continuity?
Yes
Repair or replace wiring harness, then go to the next step.
No
Go to the next step.
9
VERIFY TROUBLESHOOTING OF DTC P1189 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTCs from the PCM memory.
•  Start the engine.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
•  Perform “AFTER REPAIR PROCEDURE”.
•  Is there any DTC present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [WL-3].)
No
Troubleshooting completed.