Malfunction in Water Temperature Warning Light

METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: Malfunction in Water Temperature Warning Light
- Malfunction in Water Temperature Warning Light

DESCRIPTION

In this circuit, the meter ECU receives engine coolant temperature signals from the hybrid vehicle control ECU using the CAN communication system (CAN No. 1 Bus). The meter ECU displays engine coolant temperature that is calculated based on the data received from the hybrid vehicle control ECU.

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
* If there is an open or short in the engine coolant temperature sensor circuit, the hybrid vehicle control ECU stores the DTCs. Troubleshoot the SFI system SFI System.
* If the exhaust heat recirculation system has a malfunction, the engine coolant temperature hot warning light comes on to inform the driver of the malfunction.

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication DTC is output Diagnosis System.

Result:





B -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.

2. SYSTEM CHECK

(a) Check the coolant hot warning light.

Result:





B -- CHECK FOR DTC
A -- Continue to next step.

3. PERFORM ACTIVE TEST USING TECHSTREAM (COOLANT HOT INDICATOR)

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Combination Meter / Active Test.

(e) Check the operation by referring to the table below.

Combination Meter





OK:

Coolant hot warning light operation is normal.

NG -- REPLACE COMBINATION METER ASSEMBLY Removal
OK -- Continue to next step.

4. CHECK FOR DTC

(a) Check for DTCs.

Result:





B -- GO TO SFI SYSTEM SFI System

C -- GO TO METER / GAUGE SYSTEM B1503
A -- Continue to next step.

5. READ VALUE USING TECHSTREAM (COOLANT TEMPERATURE, COOLANT TEMP)

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream on.

(d) Enter the following menus:

(1) for Combination Meter: Body Electrical / Combination Meter / Data List.

(2) for Engine: Powertrain / Engine / Data List.

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

Combination Meter





Engine





OK:

When the Data List values of the ECUs do not match, a signal output error of the hybrid vehicle control ECU is suspected.

NG -- REPLACE HYBRID VEHICLE CONTROL ECU Removal
OK -- Continue to next step.

6. REPLACE COMBINATION METER ASSEMBLY

(a) Replace the combination meter assembly with a new or a known good one Removal.

OK:

The operation of the coolant hot warning light returns to normal.

NG -- REPLACE HYBRID VEHICLE CONTROL ECU Removal

OK -- END