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Home >> Mercury >> 2009 >> Sable Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1637 (Interior Lighting System) >> Diagnosis And Testing >> Interior Lighting >> Pinpoint Tests >> Pinpoint Test F: All The Courtesy Lamps Stay On Continuously >> Instrument Panel Dimmer Switch Input
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Instrument Panel Dimmer Switch Input

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

The SJB  monitors the instrument panel dimmer switch status to determine if the courtesy lamps are requested. When the instrument panel dimmer switch is rotated to the DOME LAMP position, ground is supplied.

The SJB  supplies voltage to the interior courtesy lamp(s) when any of the following conditions exist:

DTC DESCRIPTION CHART

DTC Description Fault Trigger Conditions
  • B1320 - Driver Door Ajar Circuit Open
An on-demand DTC that sets when the SJB  detects an open from the LH front door ajar input circuit.
  • B1328 - Passenger Door Ajar Circuit Open
An on-demand DTC that sets when the SJB  detects an open from the RH front door ajar input circuit.
  • B1336 - Door Ajar RR Circuit Open
An on-demand DTC that sets when the SJB  detects an open from the RH rear door ajar input circuit.
  • B1572 - Door Ajar LR Circuit Open
An on-demand DTC that sets when the SJB  detects an open from the LH rear door ajar input circuit.
  • B1688 - Lamp Dome Input Circuit Short to Ground
An on-demand DTC that sets when the SJB  detects a short to ground from the dome lamp request input circuit.
  • B2077 - Liftgate Ajar Switch Circuit Failure
An on-demand DTC that sets when the SJB  detects an open from the liftgate/liftgate window ajar input circuit.
  • B2A35 - Interior Lighting Output Circuit Open
An on-demand DTC that sets when the SJB  detects a short to voltage from the courtesy lamp lighting output circuit.

This pinpoint test is intended to diagnose the following: