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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 DeVille 🢒 DTC 🢒 DTC P1360

Circuit Description

There are two separate ignition module assemblies, one for each bank of cylinders. Each assembly contains an ignition control (IC) module and four ignition coils. Each IC module consists of the following circuits:

    • Ignition 1 voltage
    • Ground
    • IC timing low reference
    • IC circuits for cylinders 1-8

Each ignition coil connects directly to its spark plug via a short boot. The IC circuits transmit timing pulses from the powertrain control module (PCM) to the IC modules, which triggers the coils to fire the plugs in the correct sequence. The PCM monitors each IC circuit for improper voltage levels.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC
    • During PCM power-up, the PCM detects an open condition in the IC circuit group for the #3, #5, and #8 cylinders.
        OR
        The PCM detects a short to voltage condition in the IC circuit group for the #3, #5, and #8 cylinders.
    • The condition is present for less than 1 second.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

The Misfire Current Cyl # / Misfire History Cyl # displays on the scan tool provides information that may be useful in diagnosing DTC P1360. The Misfire Current Cyl # counter may normally display a small amount of activity (0-10 counts). However, the display should not increment steadily. The Misfire History Cyl # counter will display a very large number for the circuits with the largest failure occurrence.

If the condition is intermittent, refer to Intermittent Conditions .

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Does DTC P1359 also set?

--

Go to Step 3

Go to Step 5

3

With the engine idling, observe the Misfire Current Cyl # display on the scan tool.

Is the Misfire Current Cyl # incrementing for any even cylinders?

--

Go to Step 6

Go to Step 4

4

Is the Misfire Current Cyl # incrementing for any odd cylinders?

--

Go to Step 7

Go to Step 15

5

With the engine idling, observe the Misfire Current Cyl # display on the scan tool.

Is the Misfire Current Cyl # incrementing for two cylinders?

--

Go to Step 8

Go to Step 11

6
  1. Inspect the front bank ignition coil cassette assembly for the following conditions:
    2. • Disconnected or damaged harness connector
    • Loss of ignition module power or ground
    • Poor connections between the ignition module and harness connector
  2. If a condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

7
  1. Inspect the rear bank ignition coil cassette assembly for the following conditions:
    2. • Disconnected or damaged harness connector
    • Loss of ignition module power or ground
    • Poor connections between the ignition module and harness connector
  2. If a condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

8

Are the incrementing cylinders even (cylinders 2 and 8)?

--

Go to Step 9

Go to Step 10

9
  1. Turn OFF the ignition.
  2. Disconnect the front bank ignition coil cassette connector.
  3. Disconnect the PCM. Refer to Powertrain Control Module Replacement .
  4. Turn ON the ignition, with the engine OFF.
  5. Test cylinder 2 and 8 IC circuits for a short to voltage. Refer to Testing for a Short to Voltage in Wiring Systems.
  6. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 15

10
  1. Turn OFF the ignition.
  2. Disconnect the rear bank ignition coil cassette connector.
  3. Disconnect the PCM. Refer to Powertrain Control Module Replacement .
  4. Turn ON the ignition, with the engine OFF.
  5. Test cylinder 3 and 5 IC circuits for a short to voltage. Refer to Testing for a Short to Voltage in Wiring Systems.
  6. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 15

11
  1. Turn OFF the ignition.
  2. Disconnect the ignition coil cassette connector associated with the incrementing Misfire Current Cyl #.
  3. Connect DMM between the affected IC circuit and ground.
  4. Remove the fuel injector fuses.
  5. Measure the frequency of the affected IC circuit while cranking the engine.

Does the frequency measure within the specified values?

1-2 Hz

Go to Step 13

Go to Step 12

12
  1. Test the affected IC circuit for an open. Refer to Testing for Continuity in Wiring Systems.
  2. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 15

13
  1. Test for poor connections between the ignition module and harness connector for the affected IC circuit.
  2. If the condition is found, repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

14

Replace the appropriate ignition module. Refer to Ignition Control Module Replacement - Bank 1 or Ignition Control Module Replacement - Bank 2 .

Did you complete the replacement?

--

Go to Step 16

--

15

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

--

Go to Step 16

--

16
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

--

Go to Step 17

Go to Step 2

17

With a scan tool observe the Stored information, Capture info.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK