Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 1131

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When Monitored:
The engine running. The engine speed greater than 1000 RPM.

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Set Condition:
Battery voltage is 1 volt less than desired voltage for a set period of time. One Trip Fault. ETC light is flashing.

Possible Causes

RESISTANCE IN THE (A1) BATTERY POSITIVE CIRCUIT (A802 FUSE LINK CIRCUIT)

RESISTANCE IN THE GENERATOR CASE GROUND

GENERATOR OPERATION

(K20) GENERATOR FIELD CONTROL CIRCUIT OPEN

(K20) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND

(Z20) GROUND CIRCUIT OPEN

PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).

Diagnostic Test

1.

ACTIVE DTC

NOTE: Make sure the Battery is in good condition. Using the Midtronics Battery Tester, test the Battery
before continuing.

NOTE: Inspect the vehicle for after market accessories that may exceed the Generator System output.
Turn the ignition off.

NOTE: Make sure the generator drive belt is in good operating condition.

NOTE: Inspect the fuses in the IPM. If an open fuse is found, use the wire diagram/schematic as a guide,
inspect the wiring and connectors for damage.
Ignition on, engine not running.

With the scan tool, read DTCs.

Is the DTC active at this time?

Yes

>> Go To 2

No

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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ENGINE ELECTRICAL DIAGNOSTICS

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2.

(A1) B+ CIRCUIT HIGH RESISTANCE

WARNING: When the engine is operating, do not stand in direct
line with the fan. Do not put your hands near the pulleys, belts, or
fan. Do not wear loose clothing. Failure to follow these instruc-
tions can result in personal injury or death.

NOTE: Make sure all wires are clear of the engine’s moving parts.
Measure the voltage between the (A802) B+ Terminal at the Generator
and the (A1)Battery + Post.

Start the engine.

Is the voltage above 0.4 of a volt?

Yes

>> Repair the excessive resistance in the (A802/A11/A1) B+

circuit between the Generator and Battery.

NOTE: Inspect the (A802) fuse link circuit and the Post Pass
Through connection, ensure proper operation.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 3

3.

GENERATOR CASE GROUND HIGH RESISTANCE

Ignition on, engine not running.

Start the engine.

Allow the engine to reach normal operating temperature.

NOTE: Make sure all wires are clear of the engine’s moving parts.
Measure the voltage between the Generator case and Battery ground post.

Is the voltage above 0.1 of a volt?

Yes

>> Repair excessive resistance in the Generator Ground between the Generator Case and Battery ground

side.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 4

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ENGINE ELECTRICAL DIAGNOSTICS

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4.

GENERATOR OPERATION

Turn the ignition off.

Disconnect the Generator Field harness connector.

Using a 12-volt test light, jump it across the Generator Field harness
connector.

Ignition on, engine not running.

With the scan tool, actuate the Gen Field Control circuit.

Does the test light illuminate brightly and flash on and off?

Yes

>> Replace the Generator.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 5

5.

(K20) GENERATOR FIELD CONTROL CIRCUIT OPEN

Turn the ignition off.

Disconnect the PCM harness connectors.

CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the (K20) Gen Field Control circuit from the
Generator harness connector to the appropriate terminal of the special
tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 6

No

>> Repair the open in the (K20) Gen Field Control circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

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6.

(K20) GENERATOR FIELD CONTROL CIRCUIT SHORTED TO GROUND

Measure the resistance between the (K20) Gen Field Control circuit in
the Generator Field harness connector and ground.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K20) Gen Field Control

circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 7

7.

(Z20) GROUND CIRCUIT OPEN

Measure the resistance between the (Z20) Ground circuit in the Gen-
erator Field harness connector and ground.

Is the resistance below 5.0 ohms?

Yes

>> Go To 8

No

>> Repair the open in the (Z20) Ground circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer
to 9 - ENGINE - STANDARD PROCEDURE)

8.

PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.

Were there any problems found?

Yes

>> Repair as necessary.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Replace and program the Powertrain Control Module per Service Information.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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