Diesel Data: Automotive Repair

P1585

Diagnostic Chart (Part 1 Of 2):




Diagnostic Chart (Part 2 Of 2):




Schematic:




CIRCUIT DESCRIPTION
Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. It an improper voltage level has been detected on the output circuit which controls the stepper motor cruise control inhibit circuit, DTC P1585 will set

CONDITIONS FOR SETTING THE DTC
^ The ignition is ON.
^ An improper voltage level has been detected on the output circuit which controls the cruise control inhibit.
^ The above conditions are present for at least 30 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

DIAGNOSTIC AIDS
Check for the following conditions:
^ Poor connection at the PCM - Inspect harness connectors for the following conditions:
- Backed out terminals
- Improper mating
- Broken locks
- Improperly formed or damaged terminals
- Poor terminal to wire connection
^ Damaged harness - Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the PCM, turn ON the ignition and observe a Digital Multimeter connected between the cruise control inhibit control circuit and ground at the PCM harness connector while moving connectors and wiring harnesses related to the stepper motor cruise control module. A change in voltage will indicate the location of the malfunction.

If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. Normally, ignition feed voltage should be present on the inhibit control circuit with the PCM disconnected and the ignition turned ON.
3. Checks for a shorted component or a short to B+ on the inhibit control circuit. Either condition would result in a measured current of over 500 milliamps. Also checks for a component that is going open while being operated, resulting in a measured current of 0 milliamps.
4. Checks for a short to voltage on the inhibit control circuit.
15. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.