Circuit Description
The IPM monitors the ambient light conditions through the ambient light sensor. The ambient light sensor is a variable resistor whose resistance changes as the ambient light level around it changes. As the ambient light decreases, the resistance of the ambient light sensor increases. The value of the input will be between 5 and 250 Counts.
Conditions for Running the DTC
The ignition switch is in the ON position.
Conditions for Setting the DTC
The IPC will set the DTC B2419 when it detects that the ambient light sensor input is less than 5 counts or greater than 250 counts for three seconds.
Action Taken When the DTC Sets
The IPC will assume that the ambient light level indicates darkness for all functions needing the outside light status.
Conditions for Clearing the DTC
The IPM sees that the ambient light sensor input is between 5 and 250 Counts.
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
Perform the Lighting Systems Diagnostic System Check before continuing with the diagnosis of this DTC.
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Checks if the value that the Instrument Panel Integration Module (IPM) is reading from the ambient light sensor is within the valid range.
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Checks if the value that the Instrument Panel Integration Module (IPM) is reading from the ambient light sensor is too High.
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Checks if the value that the Instrument Panel Integration Module (IPM) is reading from the ambient light sensor is too low.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics | ||||
Did you perform the Lighting Systems Diagnostic System Check? | -- | Go to Step 2 | ||
Does the scan tool indicate that the Twilight Photocell data parameter is within the specified range? | 5 - 250 Counts | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. | Go to Step 3 | |
Does the scan tool indicate that the Twilight Photocell data parameter is greater than the specified value? | 250 Counts | Go to Step 4 | Go to Step 5 | |
Does the scan tool indicate that the Twilight Photocell data parameter is less than the specified value? | 5 Counts | Go to Step 8 | Go to Step 6 | |
5 | Test the signal circuit of the ambient light sensor 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 12 | Go to Step 9 |
6 | Test the signal circuit of the ambient light sensor for a short to voltage, 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 12 | Go to Step 7 |
7 | Test the low reference circuit of the ambient light sensor 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 12 | Go to Step 9 |
8 | Inspect for poor connections at the harness connector of the ambient light sensor. 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 12 | Go to Step 10 |
9 | Inspect for poor connections at the harness connector of the Instrument Panel Integration Module (IPM). 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 12 | Go to Step 11 |
10 | Replace the ambient light sensor. Refer to Sun Load Sensor Replacement in HVAC Systems - Automatic. Did you complete the replacement? | -- | Go to Step 12 | -- |
11 |
Important:: Perform the setup procedure for the Instrument Panel Integration Module (IPM). Refer to Body Control Module (BCM) Programming/RPO Configuration . Replace the IPM. Refer to Instrument Panel Module Replacement in Body Control System. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
