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 assembly detects a malfunction in the temperature switch that is connected to the combination meter assembly via a direct line.





HINT
This DTC is for the temperature switch which is used to detect the engine coolant temperature switch 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

(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 hybrid vehicle control ECU is suspected.

OK:

Engine coolant temperature displayed on the Techstream is 80 to 100°C (176 to 212°F) after warming up.

NG -- GO TO EXHAUST HEAT RECIRCULATION SYSTEM
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - TEMPERATURE SWITCH)

(a) Disconnect the A1 connector.

(b) Disconnect the F4 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. REPLACE TEMPERATURE SWITCH

(a) Replace the temperature switch with a new or a known good one Removal.

OK:

The operation of the combination meter assembly returns to normal.

NG -- REPLACE COMBINATION METER ASSEMBLY Removal

OK -- END