Dodge Ram Truck 1500-2500-3500. Manual — part 879

P0401-EGR SYSTEM PERFORMANCE (CONTINUED)

2.

EGR OPERATION

NOTE: If the vehicle is running rough at idle (scan tool not actuating) follow the yes path to continue.
Turn all accessories off.

Start the engine.

Allow the engine to reach normal operating temperature.

With the scan tool, enter Engine System Test, then EGR System Test.

Actuate the FLOW function in the EGR System Test.

Did the engine run rough or stall?

Yes

>> Go To 3

No

>> Go To 6

3.

EGR VALVE OPEN AT IDLE

Turn the ignition off.

Disconnect the EGR Solenoid Assembly harness connector.

Start engine. Attempt to allow the engine to idle.

Does the engine run rough or stall?

Yes

>> Inspect the EGR tube assembly. If OK, replace the EGR valve.

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

No

>> Go To 4

4.

EGR VALVE ASSEMBLY INSPECTION

Inspect the EGR Assembly for the following.

Gasket(s) for leaking

Damage and/or holes in the EGR tube(s)

Carbon build up on or near the EGR pintle and passage ways.

Obstruction in the EGR tubes.

Were any problem found?

Yes

>> Repair or replace the EGR Assembly as necessary.

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

No

>> Go To 5

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P0401-EGR SYSTEM PERFORMANCE (CONTINUED)

5.

(K35) EGR SOLENOID CONTROL CIRCUIT SHORTED TO BATTERY VOLTAGE

Turn the ignition off.

Disconnect the EGR Solenoid harness connector.

Ignition on, engine not running.

Measure the voltage on the (K35) EGR Solenoid Control circuit in the
EGR Solenoid connector.

Is the voltage above 1.0 volt?

Yes

>> Repair the short to battery voltage in the (K35) EGR Sole-

noid Control circuit.

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

No

>> Go To 10

6.

EGR SOLENOID ASSEMBLY

Disconnect the EGR Solenoid harness connector.

Using a 12-volt test light, jump across the (K35) EGR Solenoid Control
terminal and the (Z335) Ground terminal in the EGR Solenoid harness
connector.

With the scan tool, actuate the EGR solenoid.

Does the 12-volt test light flash on and off?

Yes

>> Inspect the tube(s) for obstructions and damage, repair as

necessary. If OK, replace the EGR Solenoid Assembly.

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

No

>> Go To 7

DR/DH

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P0401-EGR SYSTEM PERFORMANCE (CONTINUED)

7.

(Z335) EGR SOLENOID GROUND CIRCUIT OPEN

Turn the ignition off.

Using a 12-volt test light connected to battery voltage, probe the
(Z335) EGR Solenoid ground circuit in the EGR Solenoid harness con-
nector.

Does the 12-volt test light illuminate brightly?

Yes

>> Go To 8

No

>> Repair the open in the (Z335) EGR Solenoid ground cir-

cuit.

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

8.

(K35) EGR SOLENOID CONTROL CIRCUIT SHORTED TO GROUND

Disconnect the C2 PCM harness connector.

Measure the resistance between ground and the (K35) EGR Solenoid
Control circuit in the EGR Solenoid harness connector.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K35) EGR Solenoid

Control circuit.

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

No

>> Go To 9

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P0401-EGR SYSTEM PERFORMANCE (CONTINUED)

9.

(K35) EGR SOLENOID CONTROL CIRCUIT OPEN

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 (K35) EGR Solenoid Control circuit from
the EGR Solenoid harness connector to the appropriate terminal of
special tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 10

No

>> Repair the open in the (K35) EGR Solenoid Control circuit.

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

10.

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)

DR/DH

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