DTC B1503: Exhaust Heat Management Warning Detected: Procedure
- READ VALUE USING TECHSTREAM
- Set the vehicle in the maintenance mode using the Techstream, refer to INSPECTION MODE PROCEDURE .
- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON.
- Turn the Techstream on.
- Enter the following menus: Body Electrical / Combination Meter / Data List.
- Check the values by referring to the table below.COMBINATION METER
Tester Display Measurement Item/Range Normal Condition Diagnostic Note Coolant Temperature Engine coolant temperature/0°C to 127.5°C (32°F to 261.5°F) After warming up: 80 to 95°C (176 to 203°F) - HINT:
- The coolant temperature value in this inspection is the data sent from the engine coolant temperature sensor for the SFI system.
- When the Data List values do not match, a signal output error of the ECM is suspected.
OK
Engine coolant temperature displayed on the Techstream is 80 to 95°C (176 to 203°F) after warming up.
NG → See step 4
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (COMBINATION METER - TEMPERATURE SWITCH)
- Disconnect the P2 temperature switch connector.
- Disconnect the E1 meter connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
Tester Connection Condition Specified Condition P2-2 (TWS2) - E1-28 (TWS2) Always Below 1 Ω E1-28 (TWS2) - Body ground Always 10 kΩ or higher
NG → REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- INSPECT TEMPERATURE SWITCH
- Remove the temperature switch, refer to REMOVAL .
- Measure the resistance according to the value(s) in the table below.
Standard resistance
Tester Connection Condition Specified Condition 1 (GND) - 2 (TWS2) Temperature is 20°C (68°F) 2.32 to 2.59 kΩ 1 (GND) - 2 (TWS2) Temperature is 80°C (176°F) 0.310 to 0.326 kΩ
NG → See step 6
OK → See step 5
- GO TO EXHAUST HEAT RECIRCULATION SYSTEM. Refer to PROBLEM SYMPTOMS TABLE
- REPLACE COMBINATION METER ASSEMBLY. Refer to REMOVAL
- REPLACE TEMPERATURE SWITCH. Refer to REMOVAL