DTC P0537:00 [MZR 1.3, MZR 1.5]


id0102f8705200

DTC P0537:00

Evaporator temperature sensor circuit low input

DETECTION CONDITION
•  If the input voltage is less than 0.08 V for 16 s or more, the PCM determines that the evaporator temperature sensor circuit has a malfunction.
Diagnostic support note
•  This is a continuous monitor (other).
•  The MIL does not illuminate.
•  FREEZE FRAME DATA (Mode 2)/Snapshot data is not available.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  Evaporator temperature sensor connector or terminals malfunction
•  Evaporator temperature sensor malfunction
•  Short to ground in wiring harness between evaporator temperature sensor terminal B and PCM terminal 1AW
•  PCM connector or terminals malfunction
•  Evaporator temperature sensor signal circuit and ground circuit are shorted to each other
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
2
INSPECT EVAPORATOR TEMPERATURE SENSOR CONNECTOR CONDITION
•  Turn the ignition switch off.
•  Disconnect the evaporator temperature sensor connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 7.
No
Go to the next step.
3
CLASSIFY EVAPORATOR TEMPERATURE SENSOR MALFUNCTION OR WIRING HARNESS MALFUNCTION
•  Reconnect all disconnected connectors.
•  Access the A/CT V PID using the M-MDS.
•  Verify and compare the A/CT V PID values when disconnecting and connecting evaporator temperature sensor connector.
•  Does the A/CT V PID value change?
Yes
Inspect the evaporator temperature sensor.
•  Replace the evaporator temperature sensor, if necessary.
Go to Step 7.
No
Go to the next step.
4
INSPECT EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Evaporator temperature sensor connector is disconnected.
•  Turn the ignition switch off.
•  Inspect for continuity between evaporator temperature sensor terminal B (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 the PCM internal circuit).
Go to Step 7.
No
Go to the next step.
5
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 7.
No
Go to the next step.
6
INSPECT EVAPORATOR TEMPERATURE SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER
•  Evaporator temperature sensor and PCM connectors are disconnected.
•  Inspect for continuity between evaporator temperature sensor terminals B and A (wiring harness-side).
•  Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to each other, then go to the next step.
No
Go to the next step.
7
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the KOEO or KOER self test.
•  Is the same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
8
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.