Dodge Ram Truck 1500-2500-3500. Manual — part 890

P0442-EVAP PURGE SYSTEM MEDIUM LEAK (CONTINUED)

4.

EVAPORATIVE EMISSION LEAK DETECTION

NOTE: A thorough visual inspection of the Evap system hoses, tubes, and connections may save time in
your diagnosis. Look for any physical damage or signs of wetness at connections. The strong smell of fuel
vapors may also aid diagnosis.
To continue testing, you will need Miller Tool #8404A Evaporative Emissions Leak Detector (EELD).

Remove the Air supply hose from the service port (if equipped) or from the #8404-ADP adapter.

Connect the SMOKE supply tip (black hose) to the service port (if equipped) or to the #8404-ADP adapter.

Set the smoke/air control switch to SMOKE.

NOTE: The flow meter indicator ball will not move in the smoke mode.
Press the remote smoke/air start button.

NOTE: Make sure that smoke has filled the EVAP system by continuing to press the remote smoke/air start
button, remove the vehicle fuel cap, and wait for the smoke to exit. Once smoke is indicated reinstall the
fuel cap.

NOTE: For optimal performance, introduce smoke into the system for an additional 60 seconds; continue
introducing smoke at 15 second intervals, as necessary.
While still holding the remote smoke/air start button, use the white light (#8404-CLL) to follow the EVAP system
path, and look for the source of the leak indicated by exiting smoke.

If a leak is concealed from view (i.e., top of fuel tank), release the remote smoke/air start button, and use the ultra-
violet (UV) black light #8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that is left
behind by the smoke.

The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a
UV light.

NOTE: Carefully inspect the vent side of the EVAP Canister. Due to the filtering system in the canister the
smoke may not be as thick. Introducing smoke into the filtered side of the canister may assist in locating
the leak.

Was a leak found?

Yes

>> Repair or replace the leaking component as necessary.

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

No

>> Go To 5

5.

EVAP PURGE SOLENOID OPERATION

NOTE: After disconnecting the Evap Purge Solenoid vacuum connections, inspect the lines and solenoid for
any signs of contamination from the EVAP Canister. This may indicate a faulty check valve. Replace/repair
as necessary.
Turn the ignition off.

Disconnect the vacuum hoses at the Evap Purge Solenoid.

Using a hand vacuum pump, apply 10 in Hg to the

9

CAN

9

of the EVAP Purge Solenoid.

NOTE: Monitor the vacuum gauge for at least 15 seconds.

Does the EVAP Purge Solenoid hold vacuum?

Yes

>> Test Complete.

No

>> Replace the Evap Purge Solenoid.

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

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

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P0443-EVAP PURGE SOLENOID CIRCUIT

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

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P0443-EVAP PURGE SOLENOID CIRCUIT (CONTINUED)

For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
The ignition on or engine running. Battery voltage greater than 10 volts.

•

Set Condition:
The PCM will set a trouble code if the actual state of the solenoid does not match the intended state. One Trip
Fault. Three good trips to turn off the MIL.

Possible Causes

(K52) EVAP PURGE CONTROL CIRCUIT OPEN

(K52) EVAP PURGE SOLENOID CONTROL CIRCUIT SHORTED TO GROUND

(K70) EVAP PURGE SOLENOID SIGNAL CIRCUIT OPEN

(K70) EVAP PURGE SOLENOID SIGNAL CIRCUIT SHORTED TO GROUND

EVAP PURGE SOLENOID

PCM

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

Diagnostic Test

1.

ACTIVE DTC

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)

2.

EVAP PURGE SOLENOID OPERATION

Turn the ignition off.

Disconnect the EVAP Purge Solenoid harness connector.

Ignition on, engine not running.

Using a 12-volt test light, jump across the (K52) Evap Purge Solenoid
Control circuit and (K70) Evap Purge Solenoid Signal circuit in the
EVAP Purge Solenoid harness connector.

With a scan tool, actuate the EVAP Purge Solenoid.

Does the test light flash on and off?

Yes

>> Replace the EVAP Purge Solenoid.

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

No

>> Go To 3

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

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P0443-EVAP PURGE SOLENOID CIRCUIT (CONTINUED)

3.

(K52) EVAP PURGE SOLENOID CONTROL CIRCUIT OPEN

Turn the ignition off.

Disconnect the C3 PCM harness connector.

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 (K52) Evap Purge Solenoid Control cir-
cuit from the Evap Purge Solenoid harness connector to the appropri-
ate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 4

No

>> Repair the open in the (K52) EVAP Purge Solenoid Con-

trol circuit.

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

4.

(K52) EVAP PURGE SOLENOID CONTROL CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K52) Evap Purge
Solenoid Control circuit in the Evap Purge Solenoid harness connec-
tor.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K52) EVAP Purge Sole-

noid Control circuit.

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

No

>> Go To 5

DR/DH

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

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