Headlights - Automatic Twilight Sentinel Cadillac Seville V

DESCRIPTION & OPERATION

Twilight delay switch in headlight switch assembly is supplied a 5-volt reference from Instrument Panel Module (IPM). IPM also provides ground to twilight delay switch. Switch is a potentiometer in which resistance varies as switch is moved. IPM receives an input voltage proportional to resistance of potentiometer through twilight delay signal circuit. IPM sends a class 2 message to Dash Integration Module (DIM) indicating on/off status and delay length for twilight sentinel. With twilight sentinel switch in any position other than OFF, DIM will turn headlights on or off according to daytime/nighttime status sent by IPM. DIM uses twilight delay signal to keep headlights and park lights on after ignition switch is turned from RUN to OFF positions, during nighttime conditions.

COMPONENT LOCATIONS

For component locations, refer to illustrations. (Scheme 36)- (Scheme 41).

COMPONENT LOCATIONS

Scheme 36

Scheme 37

Scheme 38

Scheme 39

Scheme 40

Scheme 41

PRELIMINARY INSPECTION

Verify customer complaint by operating system. Visually inspect for obvious signs of mechanical and electrical damage. Inspect for blown fuses. For fuse and/or relay identification, refer to illustrations. (Scheme 42)and (Scheme 43). Inspect for loose or corroded connections, damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary. If no fault is found, perform self-diagnostics. See SELF-DIAGNOSTIC SYSTEM.

Scheme 42

Scheme 43

LIGHTING SYSTEM DIAGNOSTIC CHECK

1. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, near steering column. If scan tool powers up, go to next step. If scan tool does not power up, perform TEST A: SCAN TOOL DOES NOT POWER UP under SYSTEM TESTS in BODY CONTROL MODULES - SEVILLE article.
2. Turn ignition switch to RUN position. Using scan tool, attempt to establish communication with Dash Integration Module (DIM), Instrument Panel Module (IPM), Rear Integration Module (RIM) and Instrument Panel Cluster (IPC). If scan tool communicates with DIM, IPM, RIM and IPC, go to next step. If scan tool does not communicate with DIM, IPM, RIM and IPC, perform TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in BODY CONTROL MODULES - SEVILLE article.
3. Using scan tool, access class 2 power mode. Cycle ignition switch through all positions, while observing ignition switch power mode parameter. If ignition switch parameter matches ignition switch positions, go to next step. If ignition switch parameter does not match ignition switch positions, perform TEST C: POWER MODE MISMATCH under SYSTEM TESTS in BODY CONTROL MODULES - SEVILLE article.
4. Using scan tool, select DISPLAY DTCs function for DIM, IPM RIM and IPC. If scan tool displays any DTC, go to next step. If scan tool does not display any DTCs, repair lighting system by symptom. Perform «TWILIGHT SENTINEL INOPERATIVE»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__twilight-sentinel-inoperative) under SYSTEM TESTS.
5. If scan tool does not display any DTCs which begin with "U", go to next step. If scan tool displays any DTCs which begin with "U", perform TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in BODY CONTROL MODULES - SEVILLE article.
6. If scan tool does not display DTCs B1000, B1004, B1007, or B1009, go to next step. If scan tool displays DTCs B1000, B1004, B1007, or B1009, perform appropriate test in accordance with DTC retrieved. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in BODY CONTROL MODULES - SEVILLE article.
7. If scan tool displays DTCs B1327 or B1328, perform appropriate test in accordance with DTC retrieved. See GENERATORS & REGULATORS - SEVILLE article in STARTING & CHARGING SYSTEMS. If scan tool does not display DTCs B1327 or B1328, perform appropriate test in accordance with DTC retrieved. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__diagnostic-trouble-code-definitions) .

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC B2419: TWILIGHT PHOTOCELL CIRCUIT MALFUNCTION

Note. Ambient light sensor may also be called twilight photocell.

Description

Instrument Panel Module (IPM) monitors ambient light conditions through ambient light sensor. Ambient light sensor is a variable resistor whose resistance changes as ambient light level around it changes. As ambient light decreases, resistance of ambient light sensor increases. Value of input will be 5-250 Counts. When IPM detects that ambient light sensor input is less than 5 counts or 250 counts or more for 3 seconds, DTC B2419 will be stored. When DTC is stored, IPM will assume that ambient light level indicates darkness for all functions needing outside light status. DTC will clear when IPM senses ambient light sensor input is 5-250 counts.

Code Enable Criteria

The following must occur for DTC to run

1. Ignition switch is in RUN position.
2. Ambient light sensor input is less than 5 counts or 250 or more counts for 3 seconds.

Testing

1. If lighting diagnostic system check has been performed, go to next step. If lighting diagnostic system check has not been performed, perform «LIGHTING SYSTEM DIAGNOSTIC CHECK»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__lighting-system-diagnostic-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, near steering column. Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT PHOTOCELL data parameter in Instrument Panel Module (IPM) open/short data list. Twilight photocell data parameter should be 5-250 counts. If twilight photocell data parameter is not within specified range, go to next step. If twilight photocell data parameter is within specified range, inspect for intermittents. See «TROUBLE SHOOTING»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel).
3. Turn ignition switch to OFF position. Disconnect ambient light sensor. Ambient light sensor is located in center of instrument panel, in defroster grille. Turn ignition switch to RUN position. Using scan tool, observe twilight photocell data parameter. Twilight photocell data parameter should be 250 counts. If twilight photocell data parameter is specified value or more, go to next step. If twilight photocell data parameter is less than specified value, go to step 5.
4. Turn ignition switch to OFF position. Connect a 3-amp fused jumper wire between ambient light sensor harness connector White wire and Yellow wire terminals. Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT PHOTOCELL data parameter. Twilight photocell data parameter should be 5 counts. If scan tool indicates twilight photocell data parameter is specified value or more, go to step 6. If scan tool indicates twilight photocell data parameter is less than specified value, go to step 8.
5. Inspect White wire for a short to ground between ambient light sensor harness connector and Instrument Panel Module (IPM) harness connector C2 terminal B5. (Scheme 44) If problem does not exist, go to step 9. If problem exists, repair White wire as necessary. After repair, go to step 12.
6. Inspect White wire for an open, high resistance or short to voltage between ambient light sensor harness connector and IPM harness connector C2 terminal B5. (Scheme 44) If problem does not exist, go to next step. If problem exists, repair White wire as necessary. After repair, go to step 12.
7. Inspect Yellow wire for an open or high resistance between ambient light sensor harness connector and IPM harness connector C2 terminal B8, and splice S209. S209 is located in instrument panel harness, approximately 1.6" from ambient light sensor harness breakout. If problem does not exist, go to step 9. If problem exists, repair Yellow wire as necessary. After repair, go to step 12.
8. Inspect ambient light sensor harness connector for poor connections. If problem does not exist, go to step 10. If problem exists, repair ambient light sensor harness connector as necessary. After repair, go to step 12.
9. Inspect IPM harness connector for poor connections. If problem does not exist, go to step 11. If problem exists, repair IPM harness connector as necessary. After repair, go to step 12.
10. Replace ambient light sensor. After repair, go to step 12
11. Replace IPM, then go to next step.
12. Using scan tool, clear DTCs. Operate vehicle within code enable criteria. If DTC resets, repeat test beginning at step 2.

Scheme 44

Twilight delay pot sensor is a potentiometer. Instrument Panel Module (IPM) determines control setting based on voltage from twilight delay pot sensor. As resistance of twilight delay switch varies, voltage input to IPM changes. IPM performs a diagnostic test on twilight delay input circuit every 150 milliseconds. When IPM detects that twilight delay input is less than 5 counts, or 250 counts or more for 3 seconds, IPM will store DTC. When DTC is stored, IPM will assume that twilight switch is on, and twilight delay indicates maximum. DTC will clear when IPM senses that twilight delay input is 5-250 counts.

The following must occur for DTC to run

1. Ignition switch is turned to RUN position.
2. Instrument panel dimmer switch is set to MAXIMUM.
3. Headlights are on.

1. If lighting diagnostic system check has been performed, go to next step. If lighting diagnostic system check has not been performed, perform «LIGHTING SYSTEM DIAGNOSTIC CHECK»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__lighting-system-diagnostic-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, near steering column. Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT DELAY POT data parameter in Instrument Panel Module (IPM) open/short data list. Twilight delay pot data parameter should be 5-250 counts. If scan tool does not indicate twilight delay pot data parameter is within specified range, go to next step. If scan tool indicates twilight delay pot data parameter is within specified range, inspect for intermittents. See «TROUBLE SHOOTING»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel).
3. Turn ignition switch to OFF position. Disconnect headlight switch harness connector. Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT DELAY POT data parameter. Twilight delay pot data parameter should be 250 counts. If scan tool indicates twilight delay pot data parameter is specified value or more, go to next step. If scan tool indicates twilight delay pot data parameter is less than specified value, go to step 8.
4. Turn ignition switch to OFF position. Connect a 3-amp fused jumper wire between headlight switch harness connector terminals B3 (Yellow wire) and B5 (Purple wire). (Scheme 45) Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT DELAY POT data parameter. Twilight delay pot data parameter should be 5 counts. If scan tool indicates twilight delay pot data parameter is less than specified value, go to next step. If scan tool indicates twilight delay pot data parameter is specified value or more, go to step 9.
5. Turn ignition switch to OFF position. Remove fused jumper wire. Connect a 3-amp fused jumper wire between headlight switch harness connector terminals B1 (Light Blue/Black wire) and B5 (Purple wire). (Scheme 45) Turn ignition switch to RUN position. Using scan tool, observe TWILIGHT DELAY POT data parameter. Twilight delay pot data parameter should be 250 counts. If scan tool indicates twilight delay pot data parameter less than specified value, go to next step. If scan tool indicates twilight delay pot data parameter specified value or more, go to step 7.
6. Inspect Light Blue/Black wire for a short to ground between ground and IPM harness connector C2 terminal B12. See «WIRING DIAGRAMS»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__wiring-diagrams). If problem does not exist, go to step 12. If problem exists, repair Light Blue/Black wire as necessary. After repair, go to step 15.
7. Inspect Light Blue/Black wire for an open, high resistance or short to voltage between IPM harness connector C2 terminal B12 and headlight switch harness connector terminal B1. (Scheme 44)and (Scheme 45). If problem does not exist, go to step 11. If problem exists, repair Light Blue/Black wire as necessary. After repair, go to step 15.
8. Inspect Purple wire for a short to ground between ground and IPM harness connector C1 terminal D8. (Scheme 44) If problem does not exist, go to step 12. If problem exists, repair Purple wire as necessary. After repair, go to step 15.
9. Inspect Purple wire for an open, high resistance or short to voltage between IPM harness connector C1 terminal D8 and headlight switch harness connector B5. (Scheme 44)and (Scheme 45). If problem does not exist, go to next step. If problem exists, repair Purple wire as necessary. After repair, go to step 15.
10. Inspect Yellow wire for an open or high resistance between IPM harness connector C2 terminal B8 and headlight switch harness connector B3. (Scheme 44)and (Scheme 45). If problem does not exist, go to step 12. If problem exists, repair Yellow wire as necessary. After repair, go to step 15.
11. Inspect headlight switch harness connector for poor connections. If problem does not exist, go to step 13. If problem exists, repair headlight switch harness connector as necessary. After repair, go to step 15.
12. Inspect IPM harness connector for poor connections. If problem does not exist, go to step 14. If problem exists, repair IPM harness connector as necessary. After repair, go to step 15.
13. Replace headlight switch. After repair, go to step 15.
14. Replace IPM, then go to next step.
15. Using scan tool, clear DTCs. Operate vehicle within code enable criteria. See «CODE ENABLE CRITERIA»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel). If DTC resets, repeat test beginning at step 2.

Scheme 45

Interior light rheostat is a potentiometer. Instrument Panel Module (IPM) determines control setting based on voltage from interior light rheostat. IPM monitor voltage in instrument panel lights dimmer switch signal circuit every 150 milliseconds. When interior light rheostat is less than 17 counts or 240 counts or more on 3 consecutive tests, DTC will be stored. When DTC is stored, set dimming level to full brightness for all displays. DTC clears when IPM detects interior light rheostat is 17-240 counts.

The following must occur for DTC to run

1. Ignition switch is turned to RUN position.

1. If lighting diagnostic system check has been performed, go to next step. If lighting diagnostic system check has not been performed, perform «LIGHTING SYSTEM DIAGNOSTIC CHECK»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__lighting-system-diagnostic-check) under SELF-DIAGNOSTIC SYSTEM.
2. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, near steering column. Turn ignition switch to RUN position. Place dimmer switch in low position. Using scan tool, observe Interior Dim Pot data parameter in Instrument Panel Module (IPM) data list. Interior dim pot data parameter should be 17-240 counts. If scan tool does not indicate interior dim pot data parameter is within specified range, go to next step. If scan tool indicates interior dim pot data parameter is within specified range, inspect for intermittents. See «TROUBLE SHOOTING»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel).
3. Turn ignition switch to OFF position. Disconnect headlight switch harness connector. Turn ignition switch to RUN position. Using scan tool, observe INTERIOR DIM POT data parameter. Interior dim pot data parameter should be 240 counts. If scan tool indicates interior dim pot data parameter is specified value or more, go to next step. If scan tool indicates interior dim pot data parameter is less than specified value, go to step 8.
4. Turn ignition switch to OFF position. Connect a 3-amp fused jumper wire between headlight switch harness connector terminals B2 (Dark Green wire) and B3 (Yellow wire). (Scheme 45) Turn ignition switch to RUN position. Using scan tool, observe INTERIOR DIM POT data parameter. Interior dim pot data parameter should be 17 counts. If scan tool indicates interior dim pot data parameter is less than specified value, go to next step. If scan tool indicates interior dim pot data parameter is specified value or more, go to step 9.
5. Turn ignition switch to OFF position. Remove fused jumper wire. Connect a 3-amp fused jumper wire between headlight switch harness connector terminals B1 (Light Blue/Black wire) and B2 (Dark Green wire). (Scheme 45) Turn ignition switch to RUN position. Using scan tool, observe INTERIOR DIM POT data parameter. Interior dim pot data parameter should be 240 counts. If scan tool indicates interior dim pot data parameter is less than specified value, go to next step. If scan tool indicates interior dim pot data parameter is specified value or more, go to step 7.
6. Inspect Light Blue/Black wire for a short to ground between ground and headlight switch harness connector terminal B1. See «WIRING DIAGRAMS»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__wiring-diagrams). If problem does not exist, go to step 12 If problem exists, repair Light Blue/Black wire as necessary. After repair, go to step 15.
7. Inspect Light Blue/Black wire for an open, high resistance or short to voltage between headlight switch harness connector terminal B1 and IPM harness connector C2 terminal B12. See «WIRING DIAGRAMS»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__wiring-diagrams). If problem does not exist, go to step 11. If problem exists, repair Light Blue/Black wire as necessary. After repair, go to step 15.
8. Inspect Dark Green wire for a short to ground between ground and headlight switch harness connector terminal B2. See «WIRING DIAGRAMS»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__wiring-diagrams). If problem does not exist, go to step 12. If problem exists, repair Dark Green wire as necessary. After repair, go to step 15.
9. Inspect Dark Green wire for an open, high resistance or short to voltage between headlight switch harness connector terminal B2 and IPM harness connector C2 terminal B11. If problem does not exist, go to next step. If problem exists, repair Dark Green wire as necessary. After repair, go to step 15.
10. Inspect Yellow wire for an open or high resistance between headlight switch harness connector terminal B3 and IPM harness connector C2 terminal B8. If problem does not exist, go to step 12. If problem exists, repair Yellow wire as necessary. After repair, go to step 15.
11. Inspect headlight switch harness connector for poor connections. If problem does not exist, go to step 13. If problem exists, repair headlight switch harness connector as necessary. After repair, go to step 15.
12. Inspect IPM harness connector for poor connections. If problem does not exist, go to step 14. If problem exists, repair IPM harness connector as necessary. After repair, go to step 15.
13. Replace headlight switch. After repair, go to step 15.
14. Replace IPM, then go to next step.
15. Using scan tool, clear DTCs. Operate vehicle within code enable criteria. See «CODE ENABLE CRITERIA»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel). If DTC resets, repeat test beginning at step 2.

TWILIGHT SENTINEL INOPERATIVE

1. If lighting diagnostic system check has been performed, go to next step. If lighting diagnostic system check has not been performed, perform «LIGHTING SYSTEM DIAGNOSTIC CHECK»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel__lighting-system-diagnostic-check) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ignition switch to RUN position. Press and hold brake pedal. Move gearshift selector out of Park. Turn headlight switch off. Move twilight control out of OFF position. Cover ambient light sensor, and wait 20 seconds. Observe headlights. Uncover ambient light sensor, and expose to a bright light source. Wait 20 seconds. Observe headlights. Place gearshift selector into Park. Turn ignition switch to OFF position. If headlights do not change from low beam to Daytime Running Lights (DRL), go to next step. If headlights change from low beam to DRL, inspect for intermittents. See «TROUBLE SHOOTING»(/cadillac/seville/v-1998-2004/remont/headlights/#headlights-automatic-twilight-sentinel) .
3. If DRL operates correctly, go to next step. If DRL does not operate correctly, repair DRL as necessary. See appropriate HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article.
4. Inspect headlight switch harness connector for poor connections. If problem does not exist, go to next step. If problem exists, repair headlight switch harness connector as necessary. After repair, go to step 6 .
5. Replace headlight switch. After repair, go to next step.
6. Operate system to verify repair. If system is not operating correctly, repeat test beginning at step 2 .

REMOVAL & INSTALLATION

1. Disable air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. Pull "A" pillar trim panels away from windshield "A" pillar to disengage retainer clips. Grasp center of air outlet vent and use a flat-bladed tool to release retainers inside instrument panel outlet vents at top and bottom.
2. Remove fasteners from inside air outlet vent openings in instrument panel upper trim pad. Lift instrument panel upper trim pad upward from rear edge and over instrument cluster to disengage retainers from instrument cluster trim plate. Lift trim pad at an angle and slide rearward to disengage retainers at the front of the instrument panel. It may be necessary to push down on right front edge of trim pad to disengage retainer from carrier forward of the passenger's air bag. Disconnect harness connector and remove instrument panel upper trim pad.
3. Remove fasteners securing defroster grille to instrument panel carrier. Reposition defroster grille to disconnect twilight and sunload sensors. Disconnect harness connectors and twist each sensor 1/4 turn to remove from defroster grille. To install, reverse removal procedure.

Note. Headlight switch assembly uses skin locks which grab soft skin material of instrument panel. Skin lock feature may cause headlight switch to be hard to remove.

Remove instrument panel left end cap from door opening. Push on rear of headlight switch to disengage from instrument panel. (Scheme 46) Disconnect harness connectors and remove switch assembly. To install, reverse removal procedure.

Scheme 46

WIRING DIAGRAMS

Note. For twilight sentinel system wiring diagrams, see appropriate HEADLIGHT SYSTEMS & DAYTIME RUNNING LIGHTS article.

See also:
• SELF-DIAGNOSTIC SYSTEM
• TWILIGHT SENTINEL INOPERATIVE
• DIAGNOSTIC TROUBLE CODE DEFINITIONS
• B2419
• LIGHTING SYSTEM DIAGNOSTIC CHECK
• WIRING DIAGRAMS