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DTC B119: Twilight Photocell Circuit: Intermittents

If an intermittent Code B119 is being set, manipulate the related wiring while observing BCM data parameter BD44. See DATA DISPLAY PROCEDURE under DIAGNOSTIC MODES  under SELF-DIAGNOSTIC SYSTEM, for a list of BCM Data Parameters. If the failure is induced, the reading will jump from its normal value to a reading outside the range of 6-94%. Make certain owner is aware not to cover sensor.

NOTE: The following numbered steps refer to circled numbers on diagnostic chart. See Fig 1. For circuit identification, see Fig 2.
  1. BCM data value BD44 displays light level. The normal range is from 6-94%.
  2. If the open circuit reading changes to a shorted circuit reading after jumping the sensor terminals, the BCM and wiring are okay.
  3. By applying a ground to various points in the circuits, an open can be isolated by observing whether the parameter display can be changed from the open reading to the shorted reading.
  4. Checks to see if the shorted circuit reading is due to the circuit or the sensor. If the shorted circuit reading changes to an open circuit reading after disconnecting the sensor, the BCM and wiring are okay.
NOTE: When all diagnosis and repairs are completed, clear codes and verify operation.
Fig 1: DTC B119: Twilight Photocell Circuit Flow Chart
G00100637Courtesy of GENERAL MOTORS CORP.
Fig 2: DTC B119: Twilight Photocell Circuit Flow Chart Circuit
G00100632Courtesy of GENERAL MOTORS CORP.