Circuit Description
The Dash Integration Module (DIM) has a designated circuit for monitoring vehicle system voltage. Also, other modules monitor system voltage. The DIM sends the system voltage status to other modules that do not monitor system voltage via Class 2 message. When the DIM sets B1390, the system voltage status sent to the modules will default to 12.9 Volts.
Conditions for Running the DTC
The ignition switch is not in the OFF or CRANK mode.
Conditions for Setting the DTC
This DTC will set as current when the voltage is less than 9 volts for 1.2 seconds.
Action Taken When the DTC Sets
The modules disable the setting of "U" codes and other DTCs.
Conditions for Clearing the DTC
| • | The DTC will clear from current status when the voltage is greater than or equal to 9.4 volts for 1.2 seconds. |
| • | A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | Use the ON-Board clearing DTCs feature. |
| • | Use a scan tool. |
Diagnostic Aids
The following conditions are independent of the DTC, but will occur with the DTC set current.
| • | The battery charge indicator is illuminated on the instrument cluster. |
| • | The BATTERY VOLTS LOW message is displayed on the driver information center (DIC). |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Tests for the proper voltage at voltage sense input circuit of the DIM, if voltage is not within the proper operating range, the voltage sense circuit needs to be tested.
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Tests the ground sense circuit of the DIM.
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Tests for the proper voltage at any other module setting the DTC B1327. If voltage is not within the proper operating range, the battery positive voltage and ground circuits of the module needs to be tested.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Starting and Charging Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the voltage measure greater than the specified value? | 9.4 Volts | Go to Step 5 | Go to Step 3 |
Does the voltage measure greater than the specified value? | 9.4 Volts | Go to Step 9 | Go to Step 4 | |
4 | Measure the voltage from the voltage sense circuit of the DIM to a good ground. Does the voltage measure greater than the specified value? | 9.4 Volts | Go to Step 8 | Go to Step 7 |
Does the voltage measure greater than the specified value? | 9.4 Volts | Go to Step 9 | Go to Step 6 | |
6 | Measure the voltage between the battery positive voltage circuit of the module setting the DTC B1327 and a good ground. Does the voltage measure greater than the specified value? | 9.4 Volts | Go to Step 8 | Go to Step 7 |
7 | Test the voltage sense circuit of the module setting the code for short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9 |
8 | Test the ground sense circuit of the module setting the code for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9 |
9 | Inspect for poor connections at the harness connector of the module setting the code. 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 11 | Go to Step 10 |
10 |
Important: Perform the setup procedure for the module setting the code, if necessary. Replace the module setting the code. Refer to the appropriate Repair instructions for module replacement. Did you complete the replacement? | -- | Go to Step 11 | -- |
11 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
