Circuit Description
Ignition voltage is supplied directly to the secondary air injection (AIR) pump relay. The control module supplies the ground path to the relay control circuit via an internal solid state device called a driver. Each driver has a fault line which is monitored by the control module. When the control module commands the relay ON, the voltage on the control circuit should be near 0 volts. When the control module commands the relay OFF, the voltage on the control circuit should be near battery voltage. If the fault detection circuit senses a voltage other than what is expected, this diagnostic trouble code (DTC) will set.
The control module will monitor the control circuit for the following:
| • | A short to ground |
| • | A short to voltage |
| • | An open circuit |
| • | An open relay |
| • | An internally shorted or excessively low resistance relay |
Conditions for Running the DTC
| • | The engine is cranking or running. |
| • | The system voltage is between 9-18 volts. |
| • | The driver changes the commanded state. |
Conditions for Setting the DTC
| • | The control module detects an improper voltage level on the control circuit. |
| • | The condition exists for more than 30 seconds. |
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
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
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 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 Intermittent Conditions .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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The Diagnostic System Check prompts you to complete some basic checks and store the Freeze Frame/Failure Records data on the scan tool.
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Listen for a click when the relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
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This step tests for voltage at the feed.
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This step verifies that the control module is providing a ground.
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This step tests if ground is constantly being applied.
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The control module utilizes electrically erasable programmable read only memory (EEPROM). When the control module is replaced, the new control module must be programmed.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
Did you perform A Diagnostic System Check-Engine Controls? | Go to Step 2 | ||
Does the relay turn ON and OFF with each command? | Go to Diagnostic Aids | Go to Step 3 | |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 | |
Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 | |
Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 | |
6 | Test the control circuit for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
7 |
Important: After the repair is made, reconnect all devices and replace all open fuses. Turn ON the ignition, with the engine OFF. Use the scan tool in order to command the AIR pump and solenoid ON and OFF. If the pump does not operate, replace it. Test the control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
8 | Test for poor connections at the relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
9 | Test for poor connections at the control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
10 | Repair the open or short to ground in the feed circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the relay. Did you complete the replacement? | Go to Step 13 | -- |
|
Important: After the repair is made, reconnect all devices and replace all open fuses. Turn ON the ignition, with the engine OFF. Use the scan tool in order to command the AIR pump and solenoid ON and OFF. If the pump does not operate, replace it. Replace the PCM control module. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | Go to Step 13 | -- | |
13 |
Does the DTC run and pass? | Go to Step 14 | Go to Step 2 |
14 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK | |
