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For 1990-2009 cars only

Refer to Engine Controls Schematics

MAF, Secondary Air Injection Pump Bypass Solenoid, IAC and Secondary AIR Pump


Object Number: 590140  Size: FS
Engine Emissions Fuses
Ground G117
Ground G113
Handling ESD Sensitive Parts Notice
Engine Controls Component Views
Powertrain Control Module Description
Cruise Control Module, EBCM and VSS
Heated O2 Sensors
OBD II Symbol Description Notice
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Circuit Description

Ignition voltage is supplied directly to the AIR solenoid valve. The powertrain control module (PCM) controls the solenoid by grounding the control 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. When the PCM is commanding a component ON, the voltage of the control circuit should be near 0 volts. When the PCM is commanding the control circuit to a component OFF, the voltage potential of the circuit should be near battery voltage. If the fault detection circuit senses a voltage other than what is expected, this DTC will set.

The PCM will monitor the control circuit for the following:

    • A short to ground
    • A short to voltage
    • An open circuit
    • An internally shorted or excessively low resistance solenoid

When the PCM detects any of the above malfunctions, this DTC will set and the affected driver will be disabled.

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

Conditions for Clearing the MIL/DTC

    • The PCM turns the MIL OFF after 3 consecutive drive trips during which the diagnostic runs and passes.
    • A last test failed, or the current DTC, clears when the diagnostic runs and passes.
    • A History DTC clears after 40 consecutive warm-up cycles, if no other emission related diagnostic failures are reported.
    • Use a scan tool in order to clear the MIL diagnostic trouble code.
    • 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.

Notice: Do not operate the AIR pump for more than 60 seconds. Continuous operation of the AIR pump in excess of 60 seconds will damage the AIR pump.

If the problem is intermittent, refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Listen for an audible click when the solenoid operates. Repeat the commands as necessary.

  2. This check can detect a partially shorted coil which would cause excessive current flow. Leaving the circuit energized for 2 minutes allows the coil to warm up. When warm, the coil may open (Amps drop to 0), or short (goes above 0.75 Amp).

  3. If no trouble is found in the control circuit or the connection at the PCM, the PCM may be damaged, however, this is an extremely unlikely failure.

Step

Action

Value(s)

Yes

No

1

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

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Turn the key to ON, with the engine OFF.
  2. Command the solenoid ON and OFF with the scan tool.

Does the solenoid turn ON and OFF with each command?

--

Go to Step 3

Go to Step 5

3

  1. Turn the key to OFF.
  2. Disconnect the PCM.
  3. Turn the key to ON.
  4. Measure current from the solenoid control circuit in the PCM harness connector to ground for 2 minutes using the DMM on a 10 amp scale.

Does the current draw stay within the range shown?

0.1-0.75 A

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn the key to OFF.
  2. Disconnect the solenoid.
  3. Measure the resistance from the solenoid control circuit in the PCM harness connector to ground with the DMM .

The DMM should display an infinite resistance.

Does the DMM display an infinite resistance?

--

Go to Step 11

Go to Step 9

5

  1. Turn the key to OFF.
  2. Disconnect the solenoid.
  3. Connect a test lamp between the terminals in the harness connector.
  4. Turn the key to ON.
  5. Command the solenoid ON and OFF with the scan tool.

Does the test lamp turn ON and OFF with each command?

--

Go to Step 8

Go to Step 6

6

Probe the ignition feed circuit in the solenoid harness connector with the test lamp connected to ground.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 10

7

  1. Turn the key to OFF.
  2. Reconnect the solenoid.
  3. Disconnect the PCM.
  4. Turn the key to ON.
  5. Probe the solenoid control circuit in the PCM harness connector with a fused jumper wire connected to ground.

Does the solenoid operate?

--

Go to Step 12

Go to Step 9

8

Check for poor connections and terminal tension at the solenoid harness connector. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 14

Go to Step 11

9

Repair the solenoid control circuit.

Is the action complete?

--

Go to Step 14

--

10

Repair the ignition feed circuit to the solenoid.

Is the action complete?

--

Go to Step 14

--

11

Replace the solenoid.

Is the action complete?

--

Go to Step 14

--

12

Check for poor connections and terminal tension at the PCM harness connector. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 14

Go to Step 13

13

Important: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 14

--

14

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

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

--

Go to Step 15

Go to Step 2

15

Review Captured Info using the scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to the applicable DTC table

System OK