GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 DTC 🢒 DTC P1585 Cruise Control Inhibit Output Circuit

Object Number: 293727 Size: MF
Cruise Control Module, Vehicle Speed Sensor (VSS)
Engine Controls Components
OBD II Symbol Description Notice
ESD Notice
ESD Notice

Circuit Description

The Cruise Control module pulls the Cruise Inhibit circuit up to approximately 12 volts. When the PCM determines that cruise control is allowed, the PCM grounds the Cruise Inhibit circuit. The Cruise Control module detects the low voltage signal and enables the system. The PCM grounds the cruise inhibit circuit via an internal solid state device called a driver. The primary function of the driver is to supply the ground for the component being controlled. Each driver has a fault line which is monitored by the PCM. If the fault detection circuit senses a voltage other than what is expected, this DTC will set.

Conditions for Running the DTC
    • The ignition voltage is between 9-18 volts.
    • The engine speed is more than 80 RPM.
    • The PCM driver transitions from ON to OFF or from OFF to ON.

Conditions for Setting the DTC
    • A short to ground, an open circuit, or a short to battery voltage is detected on the control circuit.
    • The condition is present for at least 30 seconds.

Action Taken When the DTC Sets
    • The powertrain control module (PCM) stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

Conditions for Clearing the MIL/DTC
    • A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
    • A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
    • Use a scan tool in order to clear the MIL/DTC.
    • Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes.

Diagnostic Aids

Notice: Use the connector test adapter kit J 35616-A for any test that requires probing the following items:

   • The PCM harness connectors
   • The electrical center fuse/relay cavities
   • The component terminals
   • The component harness connector
Using this kit will prevent damage caused by the improper probing of connector terminals.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

If the problem is intermittent, refer to Intermittent Conditions .

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

  1. Normally, ignition feed voltage should be present on the control circuit with the PCM disconnected and the ignition turned ON.

    2.

  2. Checks for a shorted component or a short to B+ on the 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.

    3.

  3. Checks for a short to voltage on the control circuit.

    4.

  4. 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.

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to the Powertrain On Board Diagnostic (OBD) System Check

2

  1. Turn the key to Off.
  2. Disconnect the PCM.
  3. Turn the key to On.
  4. Using DMM J 39200 , measure voltage between the cruise inhibit control circuit at the PCM harness connector and ground.

Is voltage near the specified value?

B+

Go to Step 3

Go to Step 6

3

  1. Connect the DMM J 39200 to measure current between the cruise inhibit control circuit at the PCM harness connector and ground.
  2. Monitor the current reading on the digital multimeter for at least 2 minutes.

Does the current reading remain between the specified values?

0.001-0.5 amp

(1-500 mA)

Go to Step 11

Go to Step 4

4

  1. Turn the key to Off.
  2. Disconnect the stepper motor cruise control module (leave the PCM disconnected).
  3. Turn the key to On.
  4. Using the DMM J 39200 , measure voltage between the cruise inhibit control circuit and ground.

Is voltage at the specified value?

0 V

Go to Step 10

Go to Step 5

5

Locate and repair short to voltage in the cruise inhibit control circuit.

Is the action complete?

--

Go to Step 16

--

6

Check the ignition feed fuse for the stepper motor cruise control module.

Is the fuse blown?

--

Go to Step 7

Go to Step 8

7
  1. Check for a short to ground in the ignition feed circuit for the stepper motor cruise control module.
  2. Replace the fuse.

Was a problem found and corrected?

--

Go to Step 16

Go to Step 14

8
  1. Disconnect the stepper motor cruise control module.
  2. Turn the key to On.
  3. Measure voltage between the ignition feed circuit for the stepper motor cruise control module and ground.

Is voltage near the specified value?

B+

Go to Step 9

Go to Step 13

9
  1. Check the cruise inhibit control circuit for an open or a short to ground.
  2. If a problem is found, repair the cruise inhibit control circuit.

Was a problem found and corrected?

--

Go to Step 16

Go to Step 10

10
  1. Check for the following conditions:
    2. • The cruise inhibit control circuit for a poor connection at the PCM.
    • The cruise inhibit control circuit for a poor connection at stepper motor cruise control module.
    • The stepper motor cruise control module ignition feed circuit for a poor connection at the stepper motor cruise control module.
  2. If a problem is found, replace loose terminal(s) as necessary. Refer to Intermittents and Poor Connections Diagnosis in Electrical Diagnosis.

Was a problem found and corrected?

--

Go to Step 16

Go to Step 14

11
  1. Turn the key to Off.
  2. Reconnect the PCM.
  3. Disconnect the stepper motor cruise control module.
  4. Turn the key to On.
  5. Connect test light J 35616-200 between the cruise inhibit control circuit and the ignition feed circuit at the stepper motor cruise control module harness connector.
  6. Using the scan tool outputs test function, cycle the cruise inhibit output ON and OFF.

Does the test light flash ON and OFF?

--

Refer to Diagnostic Aids

Go to Step 12

12
  1. Check the cruise inhibit control circuit for a poor connection at the PCM.
  2. If a problem is found, replace loose terminal. Refer to Intermittents and Poor Connections Diagnosis in Electrical Diagnosis.

Was a problem found and corrected?

--

Go to Step 16

Go to Step 15

13

Locate and repair open in ignition feed circuit to the stepper motor cruise control module.

Is the action complete?

--

Go to Step 16

--

14

Replace the stepper motor cruise control module. Refer to On-Vehicle Service in Cruise Control.

Is the action complete?

--

Go to Step 16

--

15

Replace the PCM.

Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 16

--

16
  1. Clear DTCs with the scan tool.
  2. Turn the key to Off and wait 15 seconds
  3. Operate vehicle within the conditions that are required for this diagnostic to run. Refer to Conditions for Running the DTC.

Does the scan tool indicate that this test ran and passed?

--

Go to Step 17

Go to Step 2

17

Review Captured Info using the scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to the applicable DTC table

System OK