Circuit Description
The supercharger boost pressure is monitored and regulated under various engine operating conditions. The powertrain control module (PCM) controls the boost pressure using an output driver module (ODM) and the supercharger boost control solenoid. The supercharger boost control solenoid is connected in-line with a vacuum hose. As the PCM commands the supercharger boost control solenoid ON, vacuum is applied to the bypass valve actuator, opening the bypass valve and reducing supercharger boost pressure. Power to the solenoid is supplied through a fuse. The ground circuit is controlled by the PCM. The PCM is capable of monitoring the voltage level on an ODM circuit. If the PCM detects an improper voltage level on the supercharger boost control solenoid control circuit, DTC P0243 sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0243 Supercharger Boost Solenoid Control Circuit (L67 only)
Conditions for Running the DTC
The following conditions must be met:
| • | The ignition is in the crank or run position. |
| • | System Voltage is between 11-18 volts. |
Conditions for Setting the DTC
| • | The output state of the supercharger boost control solenoid driver detects an open or an over-temperature condition for at least 15 out of 20 samples. Each sample is 100 ms. The PCM detects that the output state of the supercharger boost control solenoid driver is incorrect or excessive current is detected for more than 2 seconds. |
| or |
| • | The output state of the supercharger boost control solenoid driver detects a short for at least 5 out of 10 samples. Each sample is 12.5 ms. The PCM detects that the output state of the supercharger boost control solenoid driver is shorted for more than 1 second. |
| • | This diagnostic runs continuously. |
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
| • | The driver information center, if equipped, may display a message. |
If a shorted condition is detected, the control module will stop activating the supercharger boost control solenoid driver for the remainder of the trip.
Conditions for Clearing the DTC
| • | 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 non-emission related diagnostic. |
| • | Clear the DTC with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This test 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, causing the amperage to drop to 0 or the coil may short, causing the amperage to rise above 800 mA.
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This step tests for a short to voltage on the control circuit.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics or Boost Control System Description Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Do you hear a click when you command the solenoid ON and OFF? | -- | Go to Step 3 | Go to Step 4 |
Does the current remain within the specified value? | 0.05-0.8 A (50-800 mA) | Go to Diagnostic Aids | Go to Step 8 | |
Is voltage at the specified value? | 0 V | Go to Step 5 | Go to Step 10 | |
5 |
Does the test lamp turn ON and OFF with each command? | -- | Go to Step 8 | Go to Step 6 |
6 |
Does the test lamp illuminate? | -- | Go to Step 7 | Go to Step 12 |
7 |
Does the solenoid operate (audible click)? | -- | Go to Step 11 | Go to Step 9 |
8 | Inspect for a poor connection at the boost control solenoid harness connector and repair as necessary. Refer to Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 15 | Go to Step 13 |
9 | Repair the boost control solenoid control circuit for an open or short to ground. Refer to Wiring Repairs in Wiring Systems. Did you complete the action? | -- | Go to Step 15 | -- |
10 | Repair the boost control solenoid control circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you complete the action? | -- | Go to Step 15 | -- |
11 | Inspect for a poor connection at the PCM harness connector containing the boost control solenoid control circuit and repair as necessary. Refer to Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 15 | Go to Step 14 |
12 | Repair the open or short to ground in the boost control solenoid ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the action? | -- | Go to Step 15 | -- |
13 | Replace the boost control solenoid. Refer to Boost Control Solenoid Replacement . Did you complete the action? | -- | Go to Step 15 | -- |
14 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 15 | -- |
15 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 16 |
16 | Observe the Capture Info with a scan tool. Are there any DTC that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |
