P2603

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P2603-768: Coolant Pump Control Circuit High

DTC P2603-768 - Coolant Pump Control Circuit High

DESCRIPTION
HINT: Although the DTC title refers to "coolant pump", this DTC is related to the oil pump control circuit.

The hybrid vehicle control ECU detects the MG1 and MG2 temperature based on signals from the generator and motor temperature sensors and activates the OIL PMP relay and oil pump driver (oil pump with motor assembly).
The hybrid vehicle control ECU monitors OPST signals from the oil pump driver and detects malfunctions.

The oil pump with motor assembly is activated when:
1. MG1 temperature is 248°F (120°C) or more
2. MG2 temperature is 266°F (130°C) or more and the MG1 temperature is 212°F (100°C) or more
HINT:
- If the second condition occurs, and the oil pump with motor assembly does not activate even though the MG1 temperature is 212°F (100°C) or more, the hybrid vehicle control ECU will attempt to activate it when the MG1 temperature changes to 230°F (110°C), 248°F (120°C), 266°F (130°C), 284°F (140°C) and 302°F (150°C) respectively.
- The oil pump cannot be activated only with the OIL PMP relay on. It is activated after receiving the command signals (OPM1) from the hybrid vehicle control ECU.

WIRING DIAGRAM

INSPECTION PROCEDURE
NOTICE:
- When troubleshooting the oil pump with motor assembly, check for the following conditions.

- ATF temperature inside the oil cooler is 41°F (5°C) or more.
- The ambient temperature sensor value is 41°F (5°C) or more.

PROCEDURE

1. CHECK FUSE (OIL PMP)

(a) Remove the OIL PMP fuse from the engine room relay block.
(b) Check for continuity of the OIL PMP fuse.
OK:
There is continuity.
NG -- REPLACE FUSE (OIL PMP)
OK -- Continue to next step.
2. CHECK OIL PMP RELAY
(a) Remove the OIL PMP relay from the No. 3 engine room relay block.

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

NG -- REPLACE OIL PMP RELAY
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - OIL PMP RELAY, OIL PMP RELAY - OIL PUMP)
(a) Disconnect the oil pump with motor assembly connector.
(b) Disconnect connector A43 from the hybrid vehicle control ECU.

Standard resistance (Check for short):

(d) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):

Standard resistance (Check for short):

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - OIL PUMP)
(a) Turn the power switch on (IG).

(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:

NOTE: Turning the power switch on (IG) with the hybrid vehicle control ECU connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
(c) Turn the power switch off.
(d) 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.
5. CHECK HYBRID VEHICLE CONTROL ECU
(a) Connect connector A43 to the hybrid vehicle control ECU.
(b) Connect the Techstream to the DLC3.
(c) Turn the power switch on (IG).
(d) Select the following menu items: Powertrain / Hybrid Control / Active Test / Inspection Mode -2WD Inspection.
(e) Turn the power switch on (READY).

(f) Measure the voltage according to the value(s) in the table below.
Standard voltage:

(g) Turn the power switch off.
(h) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- REPLACE OIL PUMP WITH MOTOR ASSEMBLY