B1503

METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: B1503: Exhaust Heat Management Warning Detected
B1503 - Exhaust Heat Management Warning Detected

DESCRIPTION

This DTC is stored when the combination meter sub-assembly detects a malfunction in the engine coolant temperature sensor that is connected to the combination meter sub-assembly via a direct line.





HINT
This DTC is for the engine coolant temperature sensor which is used to detect the engine coolant temperature for the exhaust heat recirculation system, not for the engine coolant temperature sensor which is used for the SFI system.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (COOLANT TEMPERATURE)

(a) Set the vehicle in maintenance mode using the Techstream Component Tests and General Diagnostics.

(b) Connect the Techstream to the DLC3.

(c) Turn the power switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / Combination Meter / Data List.

(f) Check the values by referring to the table below.

Combination Meter





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 75 to 100°C (167 to 212°F) after warming up.

NG -- GO TO EXHAUST HEAT RECIRCULATION SYSTEM Symptom Related Diagnostic Procedures
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (COMBINATION METER SUB-ASSEMBLY - ENGINE COOLANT TEMPERATURE SENSOR)

(a) Disconnect the G1 connector.

(b) Disconnect the L27 connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT ENGINE COOLANT TEMPERATURE SENSOR

(a) Remove the engine coolant temperature sensor Removal.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal

OK -- REPLACE METER CIRCUIT PLATE Disassembly