Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
This DTC must be active for the results of this test to be valid.
1. Perform any Service Bulletins that may apply.
2. Turn the ignition on.
3. With the scan tool, read DTCs and record on the repair order.
4. With the scan tool, read and record Environmental Data.
5. With the scan tool, erase EHPS DTCs.
6. Park the vehicle on level ground.
7. Start the engine.
8. Tun the steering wheel from stop to stop.
9. With the scan tool, read EHPS DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
  - Perform the EHPS VERIFICATION TEST. Refer to: EHPS VERIFICATION TEST .
ISOLATE AND CHECK THE (F941) IGNITION RUN/START CONTROL OUTPUT CIRCUIT FOR A SHORT TO GROUND
1. Remove Fuse 34 from Front Power Distribution Center (PDC).
2. The ignition must be off when checking a circuit for continuity to ground.
3. Isolate the (F941) Ignition RUN/START Control Output circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit.
4. Connect the negative lead of the DVOM to a known good ground.
5. With the positive lead of the DVOM, probe the circuit being tested at the EHPS C1 harness connector and check for continuity between the circuit and ground.
  NOTE:
  When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals.
  
  NOTE:
  There should be no continuity between ground and the circuit being tested.
  
  Is there continuity between ground and the circuit being tested?
  
  Yes
  - Repair the (F941) Ignition RUN/START Control Output circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
  - Perform the EHPS VERIFICATION TEST. Refer to: EHPS VERIFICATION TEST .
  No
  - Go To 3

CHECK THE (F941) IGNITION RUN/START CONTROL OUTPUT CIRCUIT FOR HIGH RESISTANCE BY LOAD TESTING THE CIRCUIT

Disconnect the component harness connector to isolate the 12.0 volt supply circuit.
Connect the positive lead of the load test tool to the 12.0 volt supply circuit at the component harness connector (A). Note: refer to the diagram below.
Connect the negative lead of the load test tool to the ground circuit of the Battery or a good chassis ground.
Make sure that the circuit being tested is being powered on. If the 12.0 volt circuit being tested is an ignition feed for example, the ignition must be on. If testing an output from a relay, verify that the relay is energized and on.

The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuitry.

NOTE:

Why load test a circuit? A load test is used to determine if a circuit is capable of carrying the amperage needed to perform properly. The 3156 bulb in the load tool illustrated, is a simple but effective method of testing circuit functionality. A 3156 Bulb has approximately 6.0 Ohms of resistance when the bulb is powered and draws approximately 2.0 amps of current. Read the CIRCUIT LOAD TESTING PROCEDURE for information on building a simple load test tool and for additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to: CIRCUIT LOAD TESTING PROCEDURES .

NOTE:

A 12-volt test light can be substituted for the load test tool, but only if the test light draws enough current to effectively load test the circuit. Many high impedance test lights draw very little amperage (less than 0.1 amps) and are not reliable to load test a circuit. To perform a proper load test of a circuit, the tool being used should draw more than approximately 0.75 amps.

NOTE:

Why perform a Voltage Drop Test? To verify with certainty there is not any resistance in the circuit being tested, perform a simple voltage drop test across the 3156 bulb of the load test tool. To do so perform the following:

1. Connect the leads of a DVOM to the alligator clips on the load test tool while the load test tool is connected in series with the circuit.
2. Compare the voltage drop across the bulb to the voltage reading across the Battery terminals.
3. The voltage dropped across the bulb should be equal to the voltage reading across the Battery terminals if there is no resistance in the circuit being tested.

Example: 2.0 Ohms of resistance in the circuit being tested will cause the voltage measurement across the bulb to be 25% less than when compared to Battery voltage. The reason for this is that the 2.0 Ohms in the circuit makes up 25% of the total circuit resistance of 8.0 Ohms. Read the CIRCUIT LOAD TESTING PROCEDURE for information on building a simple load test tool and for additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to: CIRCUIT LOAD TESTING PROCEDURES .

NOTE:

When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals.

NOTE:

Compare the brightness of the bulb in the load test tool to that of a direct connection to Battery.

Courtesy of CHRYSLER GROUP, LLC

Is the load test bulb illuminated and bright?

Yes

Go To 4

Repair the 12.0 volt circuit for an open or high resistance.
Perform the EHPS VERIFICATION TEST. Refer to: EHPS VERIFICATION TEST .

CHECK RELATED HARNESS CONNECTIONS
1. Disconnect the EHPS Module harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Connect the EHPS Module harness connectors. Be certain that the harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect the related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read EHPS Module DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Electro-Hydraulic Power Steering (EHPS) Module in accordance with the Service Information. Refer to MODULE, ELECTRO-HYDRAULIC POWER STEERING (EHPS), REMOVAL AND INSTALLATION .
  - Perform the EHPS VERIFICATION TEST. Refer to: EHPS VERIFICATION TEST .
  No
  - Perform the EHPS VERIFICATION TEST. Refer to: EHPS VERIFICATION TEST .
  - Test complete.