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B - Test




B: Powertrain Control Module (PCM) Power Relay

B: Introduction
B - Introduction



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B1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)

Is DTC P0562, P0685, P068A, P2531, P2533 or P2535 present?

YES
For DTC P0562, GO to B8
.

For DTCs P0685 or P068A, GO to B9
.

For DTCs P2531 and P2533, GO to B2
.

For DTC P2535, GO to B6.

NO
GO to B8.


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B2 CHECK THE KEYST PIDS

- Access the PCM and monitor the KEYST PID.
- Access the GEM/SJB and monitor the IGN_SW PID.
- Key ON, engine OFF.

Do both PIDs indicate RUN?

YES
GO to B5.

NO
GO to B3.


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B3 CHECK THE IGNITION SWITCH AND HARNESS FOR AN OPEN

- PCM connector disconnected.
- SJB-A connector disconnected.
- Key ON, engine OFF.
- Measure the voltage between:





- Measure the voltage between:





Are the voltages greater than 10 V?

YES
GO to B4.

NO
CHECK for a damaged ignition switch.

REFER to Ignition Switch Component Testing.

If the ignition switch is OK, REPAIR the open circuit.

CLEAR the DTCs. REPEAT the self-test.


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B4 CHECK THE ISP-R CIRCUIT FOR A SHORT TO GROUND

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





Is the resistance greater than 10K ohms?

YES
CHECK the ignition switch for a short to ground.

If the ignition switch is OK and DTC P2531 is present, GO to B5
.

If the ignition switch is OK and DTC P2533 is present, GO to B9.

NO
REPAIR the circuit.

CLEAR the DTCs. REPEAT the self-test.


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B5 CHECK THE PCMRC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

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





Is the resistance greater than 10K ohms?

YES
GO to B15.

NO
REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.


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B6 DTC P2535: CHECK FOR CORRECT KEY OPERATION

- Key ON, engine OFF.

Does the engine start with the key in ON position?

YES
GO to B7.

NO
GO to B15.


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B7 CHECK THE ISP-R/S CIRCUIT FOR A SHORT TO VOLTAGE

- Key in OFF position.
- PCM connector disconnected.
- Key ON, engine OFF.
- Measure the voltage between:





Is the voltage less than 1 V?

YES
GO to B16.

NO
CHECK for a damaged ignition switch.

REFER to Ignition Switch Component Testing.

If the ignition switch is OK, REPAIR the circuit.

CLEAR the DTCs. REPEAT the self-test.


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B8 CHECK THE B+ VOLTAGE TO PCM POWER RELAY

- Key in OFF position.
- PCM Power Relay connector disconnected.
- Key ON, engine OFF.
- Measure the voltage between:





Is the voltage greater than 10 V?

YES
GO to B9.

NO
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.


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B9 DTCS P0685 AND P068A: CHECK THE PCMRC CIRCUIT FOR AN OPEN IN THE HARNESS

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





Is the resistance less than 5 ohms?

YES
GO to B10.

NO
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.


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B10 CHECK THE PCMRC CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS

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





Is any voltage present?

YES
REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.

NO
For DTCs P0685 or P068A, GO to B15
.

For DTC P2533, GO to B16
.

For all others, GO to B11.


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B11 CHECK THE ISP-R VOLTAGE AT THE PCM HARNESS CONNECTOR

- Measure the voltage between:





Is the voltage greater than 10 V?

YES
GO to B12.

NO
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.


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B12 CHECK THE ISP-R CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS

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





Is any voltage present?

YES
REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.

NO
GO to B13.


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B13 CHECK THE INJPWRM CIRCUIT FOR AN OPEN IN THE HARNESS

- Fuel Injector connector disconnected.
- Measure the resistance between:





Is the resistance less than 5 ohms?

YES
GO to B14.

NO
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.


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B14 CHECK FOR AN OPEN VPWR CIRCUIT BETWEEN THE PCM AND THE PCM POWER RELAY

- Measure the resistance between:





Is the resistance less than 5 ohms?

YES
INSTALL a new PCM Power relay.

CLEAR the DTCs. REPEAT the self-test.

NO
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.


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B15 CHECK THE ISP-R AND ISP-R/S CIRCUITS FOR INTERMITTENT CONCERNS

- Key in OFF position.
- PCM connector connected.
- Key ON, engine OFF.
- Access the PCM and monitor the KEYST PID.
- Access the GEM/SJB and monitor the IGN_SW PID.
- Turn the key to the ON and START positions, while observing the PIDs.
- 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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B16 CHECK FOR CORRECT PCM OPERATION

- Key in OFF position.
- 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), Programming the VID Block for a Replacement PCM.

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