Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B1395 03: Voltage Below ThresholdDTC B1395 07: Voltage Above Threshold
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Dome/Reading Lamp Supply Voltage | 1 | 1 | -- | -- |
Dome/Reading Lamp Control | B2615 00 | B2615 00 | -- | -- |
Stop Lamp Switch Signal | B1395 03, B3600 03 | -- | -- | -- |
I/P Dimming Voltage Reference | B1395 03, B3600 03 | B1395 03, B2652 00, B3600 03 | B1395 07 | -- |
Courtesy Lamp Voltage Reference | B2615 00, B2615 02 | B2615 00, B2615 04 | B2615 00, B2615 01 | -- |
LED Dimming Voltage Reference | B2610 00, B2610 02 | B2610 00, B2610 04 | B2610 00, B2610 01 | -- |
LED Indicator Dimming Volage Reference | B2625 00 | B2625 00 | B2625 00 | -- |
Dome Lamp Switch Signal | 2 | 2 | 2 | -- |
Left Front Door Open Switch Signal | 3 | 3 | 3 | -- |
Left Rear Door Open Switch Signal | 4 | 4 | 4 | -- |
Right Front Door Open Switch Signal | 3 | 3 | 3 | -- |
Right Rear Door Open Switch Signal | 4 | 4 | 4 | -- |
Exterior Lamps Illumination Supply Voltage | 5 | 5 | 5 | -- |
Inadvertent Power Control | 5 | 5 | 5 | -- |
I/P Lamps Dimming Control | B2652 00 | B2652 00 | B2652 00 | -- |
Dome/Reading Lamp Low Control - Driver Door | -- | 1 | -- | -- |
Dome/Reading Lamp Low Control - Passenger Door | -- | 1 | -- | -- |
Exterior Lamps Low Reference | -- | 5 | -- | -- |
I/P Dimmer Switch Ground | -- | 2 | -- | -- |
LH Vanity Mirror Courtesy Lamp Ground | -- | 1 | -- | -- |
Overhead Console Courtesy Lamp Ground | -- | 1 | -- | -- |
Rear Dome Lamp Ground | -- | 1 | -- | -- |
RH Vanity Mirror Courtesy Lamp Ground | -- | 1 | -- | -- |
1. Courtesy Lamps Malfunction 2. Dome Lamp Switch Malfunction 3. Door Open Switch Malfunction - Front 4. Door Open Switch Malfunction - Rear 5. Exterior Lamps Malfunction | ||||
Circuit/System Description
Voltage for the interior backlighting components and stop lamp switch activation signal is supplied from the body control module (BCM). The BCM applies a voltage reference through the instrument panel (I/P) dimming voltage reference circuit to the interior lamp dimming switch, which is part of the headlamp switch. When the dimming switch is placed in the desired position, the dimmed voltage setting is applied from the interior lamp dimming switch through the I/P dimming control circuit to the BCM. The BCM then applies the dimmed voltage to the I/P lamps supply voltage circuit and they dim to the correct level.
The stop lamp switch is also supplied voltage on the same circuit for a stop lamp OFF signal to the BCM. When the stop lamp switch is activated the voltage signal circuit to the BCM is opened prompting the BCM to illuminate the stop lamps.
Conditions for Running the DTC
| • | Battery voltage must be between 9-16 volts. |
| • | Ignition must be ON. |
Conditions for Setting the DTC
B1395 03
The BCM detects a voltage that is lower than 0.33 volt on the I/P dimming voltage reference circuit.
B1395 07
The BCM detects a voltage that is greater than 4.97 volts on I/P dimming voltage reference circuit.
Action Taken When the DTC Sets
| • | The I/P lamps are dim or not illuminated. |
| • | The I/P lamps will not dim. |
| • | The stop lamps are always ON. |
Conditions for Clearing the DTC
| • | The conditions for setting the DTC are no longer present. |
| • | A history DTC clears after 100 malfunction-free ignition cycles. |
| • | The BCM receives the clear code command from the scan tool. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Interior Lighting Systems Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the headlamp and panel dimmer switch.
- Ignition OFF, verify that a test lamp illuminates between the ground circuit terminal 8 and B+.
- Ignition ON, verify the scan tool Dimming Control Signal parameter is less than 0.1 volts.
- Ignition ON, test for 12 volts between the I/P dimming voltage reference circuit terminal 15 and ground.
- Install a 3A fused jumper wire between the signal circuit terminal 13 and the voltage reference circuit terminal 15. Verify the scan tool BCM Dimming Control Signal parameter is greater than 2.6 volts.
- If all circuits test normal, test or replace the headlamp and panel dimmer switch.
| ⇒ | If the test lamp does not illuminate, test the ground circuit for an open/high resistance. |
| ⇒ | If greater than the specified range, test the signal circuit terminal 13 for a short to voltage. If the circuit tests normal, replace the BCM. |
| ⇒ | If less than the specified value, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
| ⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
