P1547

Article Updated by TSB-05-13-013

DTC P1547: DOR Radiator Tampering Monitor (Rationality Check)

Radiator Sensor Circuit Part 1:

Radiator Sensor Circuit Part 2:

CIRCUIT OPERATION
- The battery voltage is applied from the ignition switch to the radiator sensor (terminal No.3), and it is grounded to the vehicle body from the radiator sensor (terminal No.1).
- The radiator sensor (terminal No.2) sends the sensor signal to the powertrain control module (terminal No.3).

MONITOR EXECUTION
- Once per driving cycle

MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Not applicable

Sensor (The sensor below is determined to be normal)
- Not applicable

DTC SET CONDITIONS

Logic Flow Chart:

Logic Flow Chart

Check Condition
- Battery positive voltage is higher than 11 volts.
- Intake air temp from 0 degrees C (32 degrees F) to 40 degrees C (104 degrees F).
- Engine coolant temperature is less than 40 degrees C (104 degrees F) when the engine started.
- The engine coolant temperature - intake air temperature is 5 degrees C (41 degrees F) or less at engine start.
- When the engine coolant temperature is 77 degrees C (171 degrees F) or higher under the following conditions.
1. Drive the vehicle at the engine speed of 1,700 r/min or more for 10 minutes.
2. The engine load is 30 percent or more.

Judgement Criteria
- The temperature difference between thermistor 1 and thermistor 2 is 6 degrees C (43 degrees F) or more.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle Pattern 18. OBD-II Drive Cycle Pattern Lists

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
- Tampering of the DOR radiator

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. DOR radiator sensor installation check

- Check that the sensor is installed securely and operates normally.

Q: Is the check result normal?

YES: Go to Step 2.

NO: Replace the DOR radiator. Then go to Step 3.

STEP 2. Replace the DOR radiator

1. Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 18. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P1547 set?

YES: Replace the PCM. Then go to Step 3.

NO: The procedure is complete.

STEP 3. Perform the OBD-II drive cycle.

1. Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle Pattern 18. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P1547 set?

YES: Repeat the troubleshooting.

NO: The procedure is complete.