KU - Test

KU: Heater Pump Control

KU: Introduction KU - Introduction



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KU1 DIAGNOSTIC TROUBLE CODE (DTC) P2600: VERIFY THAT THE CONCERN IS PRESENT

Is DTC P2600 present in the KOEO or KOER self-test?

YES
GO to KU2.

NO
GO to KU8.


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KU2 CHECK THE FUNCTIONALITY OF THE HPCR CIRCUIT AT THE RELAY

- Key in OFF position.
- HPCR connector disconnected.
- Connect a non-powered test lamp between:





- Key ON, engine OFF.
- Access the PCM and control the HPUMP PID.
- Cycle the HPCR PID on and off.

Does the test lamp illuminate on and off when the HPCR output is commanded on and off?

YES
GO to KU3.

NO
GO to KU5.


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KU3 CHECK THE VPWR VOLTAGE TO HPCR

- Measure the voltage between:





Is the voltage greater than 10.5 V?

YES
GO to KU4.

NO
REPAIR the circuit. CHECK the condition of related fuses/fuse links. If damaged, CHECK the VPWR circuit for a short to ground.

CLEAR the DTCs. REPEAT the self-test.


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KU4 CHECK THE HPCR RELAY RESISTANCE

- Key in OFF position.
- Measure the resistance between:





Is the resistance between 40 - 90 ohms?

YES
Unable to duplicate or identify the concern at this time.

GO to KU8.

NO
INSTALL a new HPCR. CLEAR the DTCs. REPEAT the self-test.


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KU5 CHECK THE HPCR CIRCUIT FOR AN OPEN CIRCUIT IN THE HARNESS

- Key in OFF position.
- PCM connector disconnected.
- Measure the resistance between:





Is the resistance less than 5 ohms?

YES
GO to KU6.

NO
REPAIR the circuit.

CLEAR the DTCs. REPEAT the self-test.


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KU6 CHECK THE HPCR CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS

- Key ON, engine OFF.
- Measure the voltage between:





Is the voltage less than 1 V?

YES
GO to KU7.

NO
REPAIR the circuit.

CLEAR the DTCs. REPEAT the self-test.


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KU7 CHECK THE HPCR CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

- Key in OFF position.
- Measure the resistance between:





Is the resistance greater than 10K ohms?

YES
GO to KU9.

NO
REPAIR the circuit.

CLEAR the DTCs. REPEAT the self-test.


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KU8 CHECK THE HPCR CIRCUIT FOR AN INTERMITTENT CONCERN

- PCM connector connected.
- HPCR connector connected.
- Key ON, engine OFF.
- Access the PCM and monitor the HPUMP PID.
- Command the HPCR ON.
- Access the PCM and monitor the HPUMP_F PID.
- Carefully wiggle all accessible wiring and connectors associated with the circuit and look for a change in the PID state.

Is a concern present during the wiggle test?

YES
REPAIR as necessary.

CLEAR the DTCs. REPEAT the self-test.

NO
GO to Pinpoint Test Z Z - Introduction.


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KU9 CHECK FOR CORRECT PCM OPERATION

- Disconnect all the PCM connectors.
- Visually inspect for:

- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test and verify the concern is still present.

Is the concern still present?

YES
INSTALL a new PCM.

REFER to Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Flash Electrically Erasable Programmable Read Only Memory (EEPROM).

NO
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.