Instrument Panel Buick LeSabre VII

DESCRIPTION & OPERATION

The Instrument Panel Cluster (IPC) uses an electric analog speedometer with stepper motor-driven odometer, analog fuel gauge and indicator lights. The IPC is backlit for nighttime illumination. Some models may be equipped with analog coolant temperature gauge, oil pressure gauge and voltmeter. For speedometer testing, see the appropriate TESTS W/CODES article in the ENGINE PERFORMANCE section. See the following list.

1. Park Avenue, see: «TESTS W/CODES»(ref-19830)
2. LeSabre, see: «TESTS W/CODES»(/buick/lesabre/vii-1992-1999/remont/testing-diagnostics/#engine-controls-tests-wcodes)

Note. Some models use a Powertrain Control Module (PCM) rather than an Electronic Control Module (ECM). Aside from electronic engine controls, the modules also differ in that the PCM controls electronic transmission internals and cruise control system. Unless specifically stated, references to ECM also apply to PCM-equipped vehicles.

AIR BAG PRECAUTIONS

Observe the following precautions when working on vehicles equipped with Supplemental Inflatable Restraint (SIR) air bag systems

1. Before performing any instrument panel testing, diagnosis or repair, disable SIR system by disconnecting negative battery cable and Yellow 2-pin connector at base of steering column.
2. Wait 2 MINUTES before making repairs. SIR system retains enough voltage, for a short time after disconnecting power, to deploy air bag.
3. To avoid accidental air bag deployment, avoid SIR wiring harness when trouble shooting instrument panel components. All SIR wires are color-coded Yellow.

TESTING

Note. For speedometer testing, see the appropriate TESTS W/CODES article in the ENGINE PERFORMANCE section. For instrument panel cluster connector and terminal identification (Scheme 1) Also, see the following list.

1. Park Avenue, see: «TESTS W/CODES»(ref-19830)
2. LeSabre, see: «TESTS W/CODES»(/buick/lesabre/vii-1992-1999/remont/testing-diagnostics/#engine-controls-tests-wcodes)

Scheme 1

Base Cluster

1. Turn ignition off. Disconnect instrument cluster connector(s). Turn ignition on. Measure voltage between instrument cluster connector Pink wire at terminal B1 and ground. If battery voltage is not present, check Pink wire for an open circuit.
2. If battery voltage is present, measure voltage between instrument cluster connector Pink wire at terminal B1 and Black wire at connector terminals B6 and B8. If battery voltage is not present, check Black wire(s) for an open circuit.
3. If battery voltage is present, measure voltage between instrument cluster connector C2 Pink wire at terminal B5 and Black/White wire at connector terminal B2. If battery voltage is not present, check Black/White wire for an open circuit.
4. If battery voltage is present, measure voltage between instrument cluster connector Pink wire at terminal B5 and ground. If battery voltage is not present, check Pink wire for an open circuit.
5. If battery voltage is present, go to step 6). If battery voltage is not present, check Brown wire for an open circuit.
6. Turn ignition off. Measure voltage between instrument cluster connector terminal A5 (Orange wire) and ground. If battery voltage is not present, check Orange wire for an open circuit.
7. If battery voltage is present, check instrument cluster connector for good terminal contact at terminals A5, B1, B2, B5, B6, or B8. If terminal contact is okay, replace instrument cluster.

Gauge Cluster

1. Turn ignition off. Disconnect instrument cluster connector. Turn ignition on. Measure voltage between instrument cluster connector terminal A9 (Pink wire) and ground. If battery voltage is not present, check Pink wire for an open circuit.
2. If battery voltage is present, measure voltage between instrument cluster connector terminal B10 (Pink wire) and ground. If battery voltage is not present, check Pink wire for an open circuit.
3. If battery voltage is present, measure voltage between instrument cluster connector terminal B2 (Pink wire) and ground. If battery voltage is not present, check Pink wire for an open circuit.
4. If battery voltage is present, measure voltage between instrument cluster connector terminal A9 (Pink wire) to terminal A11 (Black/White wire), then terminal B3 (Black/White wire). If battery voltage is not present in both cases, check Black/White wires for an open circuit. If battery voltage is present, check instrument cluster connector for good contact at terminals B10, A9, B2, A11, and B3. If all circuits are okay, replace instrument cluster.

1. Turn ignition off. Disconnect instrument cluster connector. Put headlight switch in PARK or HEAD position. Put dimmer switch in LO position. Check for good terminal contact at instrument cluster connector terminal B4 and repair as necessary.
2. If terminal contact is okay, measure voltage at Gray wire between instrument cluster connector terminal B4 and ground while adjusting dimmer control. If voltage varies with dimmer control, replace instrument cluster.
3. If voltage does not vary with dimmer control, connect test light between voltage and instrument cluster connector Gray wire at terminal B4. If test light lights, repair short to ground in Gray wire. If test light does not light, check for open circuit in Gray wire and repair as necessary. If circuit is okay, replace headlight switch.

1. Turn ignition switch to OFF position. Disconnect fuel gauge sender connector. Connect 2 Red leads of Gauge Tester (J-33431) to fuel gauge sender connector terminals "B" (Purple wire) and "D" (Black wire). Turn ignition switch to RUN position.
2. Set resistance dials on tester to zero ohms (Empty), then to 90 ohms (Full). If fuel gauge fluctuates from empty to full, check for poor connections at fuel gauge sender or for damage to pigtail wiring and repair as necessary. If connections and pigtail wiring are okay, replace fuel gauge sender.
3. If fuel gauge does not fluctuate from empty to full, turn ignition off. Disconnect tester. Disconnect instrument cluster connector. Connect test light between cluster connector Purple wire terminal B3 and battery voltage. If test light lights, check Purple wire for a short to ground.
4. If test light does not light, leave test light connected and connect jumper wire between fuel gauge sender connector terminal "B" (Purple wire) and ground. If test light does not light, check Purple wire for an open circuit.
5. If test light lights, connect test light between fuel gauge sender connector terminal "D" (Black wire) and voltage. If test light lights, check Black wire for an open circuit. If test light does not light, check for good terminal contact at instrument cluster connector. If terminal contact is okay, replace instrument cluster.

1. Turn ignition off. Disconnect fuel gauge sender connector. Connect 2 Red leads from Gauge Tester (J-33431) to terminals "B" (Purple wire) and "D" (Black/White wire). Turn ignition on. Set tester resistance dials to zero ohms (empty), then 90 ohms (full). If fuel gauge does not display "E" at zero ohms and "F" at 90 ohms, go to next step. If fuel gauge does display "E" at zero ohms and "F" at 90 ohms, check fuel gauge sender connector and pigtail harness for good terminal contact. If terminal contact is okay, replace fuel gauge sender.
2. Check Purple wiring for a short to ground, open circuit, or high resistance. Check Black/White wire for open circuit or high resistance. Check all connectors and circuits for good terminal contact. If all circuits are okay, replace instrument cluster.

1. Turn ignition off. Disconnect coolant temperature sensor connector. Connect 2 Red leads of Gauge Tester (J-33431) to coolant temperature sensor harness connector terminal "A" (Light Green wire) or terminal "C" (Light Green wire). Turn ignition on.
2. Set gauge tester resistance dials to 1365 ohms, then to 55 ohms. Coolant temperature gauge should indicate cold, then hot. If gauge responds as specified, check connector for good terminal contact. If terminal contact is okay, replace coolant temperature sensor.
3. If gauge does not respond as specified, turn ignition off. Disconnect tester. Disconnect instrument cluster connector. Connect test light between cluster connector terminal C8 (Light Green wire) and voltage. If test light lights, check Light Green wire for a short to ground.
4. If test light does not light, leave test light connected. Connect jumper wire between coolant temperature sensor connector terminal "A" (Light Green wire) or "C" (Light Green wire) and ground. If test light does not light, check Light Green wire for an open circuit. If test light lights, check for good terminal contact at instrument cluster connector. If terminal contact is okay, replace instrument cluster.

1. Turn ignition off. Disconnect coolant temperature sensor connector or digital engine coolant temperature sensor. Connect one Red lead of Gauge Tester (J-33431) to sensor connector Light Green, Dark Green/White, or Dark Green wire terminal. Connect other Red lead to ground. Turn ignition on.
2. Set gauge tester resistance dials to 1400 ohms, 93 ohms, then 55 ohms. Coolant temperature gauge should indicate cold, midscale, then hot. If gauge responds as specified, check all connectors and wiring for good terminal contact. If terminal contact is okay, replace coolant temperature sensor or digital engine coolant temperature sensor.
3. If gauge does not respond as specified, turn ignition off. Check Light Green or Dark Green/White wiring for a short to ground. Check instrument cluster connector for good terminal contact. If all circuits are okay, replace instrument cluster.

CHECK OIL LEVEL INDICATOR STAYS LIT WITH OIL LEVEL OKAY

1. Turn ignition off. Disconnect oil level module connector. Turn ignition on. If indicator lights, check for short to ground in Brown/White wire.
2. If indicator does not light, turn ignition off. Check resistance between oil level module connector terminals No. 3 (Brown wire) and No. 2 (Red/White wire).
3. If resistance measures approximately 3,830 ohms, go to next step. If resistance does not measure approximately 3,830 ohms, check for open circuit or high resistance in Brown and Red/White wires. If wires and connections are okay, replace low oil level sensor.
4. Measure voltage between oil level module connector terminals No. 1 (Orange/Black wire) and No. 2 (Red/White wire). If voltmeter measures 1-2 volts in one direction only, go to next step. If voltmeter does not measure 1-2 volts in one direction only, check Orange/Black wiring for an open circuit. Check all connectors for good terminal contact. If all circuits are okay, replace oil level sensor.
5. Measure resistance between oil level module connector terminals No. 3 (Brown wire), No. 2 (Red/White wire), and No. 1 (Orange/Black wire). If any measurement is 5 ohms or less, check wiring for a short to ground. If any measurement is greater than 5 ohms, check oil level module connector for good terminal contact. If terminal contact is okay, replace oil level module.

1. Disconnect oil level module connector. Connect test light between module connector terminal No. 10 (Orange wire) and ground. Turn ignition on. If test light does not light, check Orange wire for an open circuit.
2. Connect test light between module connector terminal No. 9 (Brown wire) and ground. If test light does not light, check Brown wire for an open circuit. If test light lights, connect test light between module connector terminal No. 6 (Brown/White wire) and ground. Turn ignition on. If test light does not light, check Brown/White wire for an open circuit. Check CHECK OIL light bulb for an open circuit. Check instrument cluster connector for good terminal contact. If all are okay, replace instrument cluster.
3. If test light lights, connect test light between module connector terminals No. 6 (Brown/White wire) and No. 5 (Black/White wire). If test light does not light, check Black/White wire for an open circuit. If test light lights, measure resistance between oil level module connector terminal No. 3 (Brown wire) and No. 2 (Red/White wire). If about 3830 ohms are not present, check Brown and Red/White wires for an open circuit. Also check all connectors and wiring for an open circuit. If all circuits are okay, replace low oil level sensor.
4. If about 3830 ohms are present, check voltage between oil level module connector terminal No. 1 (Orange/Black wire) and No. 2 (Red/Black wire). If voltmeter indicates about 1-2 volts in one direction only, check oil level module connector for good terminal contact. If terminal contact is okay, replace oil level module.
5. If voltmeter does not indicate about 1-2 volts in one direction only, check Orange/Black wire for an open circuit. Check all connectors and low oil level sensor connector for good terminal contact. If all circuits are okay, replace low oil level sensor.

1. Turn ignition off. Disconnect oil level module connector. Connect fused jumper wire between oil level module connector terminal No. 6 (Brown/White wire) and ground. Turn ignition on. If indicator does not light, check Brown/White wire for open circuit or high resistance. Check all connectors for good terminal contact. If all circuits are okay, replace instrument cluster.
2. If indicator does light, measure voltage between oil level module connector terminals No. 1 (Orange/Black wire) and No. 2 (Red/White wire). If voltmeter indicates 1-2 volts in one direction only, go to next step. If meter does not indicate 1-2 volts in one direction only, check Orange/Black and Red/White wires for an open circuit or high resistance. Check all connectors for good terminal contact. If all circuits are okay, replace low oil level sensor.
3. Measure voltage between oil level module connector terminal No. 9 (Brown wire) and ground. If battery voltage is not present, check Brown wire for an open circuit, high resistance, or short to ground. If battery voltage is present, measure voltage between oil level module connector terminal No. 10 (Orange wire) and ground.
4. If battery voltage is not present, check Orange wire for an open circuit, high resistance, or short to ground. If battery voltage is present, measure voltage between oil level module connector terminal No. 10 (Orange wire) and terminal No. 5 (Black wire). If battery voltage is not present, check Black/White wire for an open circuit or high resistance. If battery voltage is present, check oil level module connector for good terminal contact at terminals No. 4, 5, 6, 9, and 10. If terminal contact is okay, replace oil level module.

LOW COOLANT INDICATOR IS LIT WITH COOLANT LEVEL OKAY

1. Turn ignition off. Disconnect oil level module connector. Start engine. If LOW COOLANT indicator is still on, check Yellow/Black wire for a short to ground. If wire is okay, replace instrument cluster. If LOW COOLANT indicator is not on, go to next step.
2. Turn ignition off. Measure resistance between oil level module connector terminals No. 2 (Red/White wire) and No. 8 (Light Green wire). If resistance is about 4990 ohms, go to next step. If resistance is not about 4990 ohms, check Light Green and Red/White wires for an open circuit or high resistance. Also check low coolant sensor connector for good terminal contact. If all circuits are okay, replace low coolant sensor.
3. Measure resistance between oil level module connector terminal No. 2 (Red/White wire) and ground, terminal No. 7 (Brown wire) and ground, and terminal No. 8 (Light Green wire) and ground. If any measurement is 5 ohms or less, check suspect wiring for a short to ground. If any measurement is greater than 5 ohms, check oil level module connector for good terminal contact. If terminal contact is okay, replace oil level module.

LOW COOLANT INDICATOR DOES NOT LIGHT WITH LOW COOLANT

CONDITION

1. Turn ignition switch to OFF position. Disconnect oil level module connector. Connect a jumper wire between oil level module connector terminal No. 4 (Yellow/Black wire) and ground. Turn ignition on.
2. If low coolant indicator does not light, check for open or high resistance in Yellow/Black wire. Also check for poor connection at instrument cluster connector C1 terminal D14 (Black wire). If Yellow/Black wire and instrument cluster connector are okay, replace instrument cluster.
3. If low coolant indicator lights, check voltage between oil level module connector terminals No. 2 (Red/White wire) and No. 7 (Brown wire). If voltmeter measures approximately 1-2 volts in one direction only, go to step 5).
4. If voltage is not as specified, check for open or high resistance in Red/White or Brown wires. Also check for poor connections at low oil level sensor and splice connections. If Red/White and Brown wires, and connections are okay, replace low oil level sensor.
5. Check voltage between oil level module connector terminal No. 9 (Brown wire) and ground. If battery voltage is present, go to next step. If battery voltage is not present, check for blown fuse No. 5A (10-amp) in instrument panel fuse block. Also check for open, high resistance or short to ground in Brown wire. Repair or replace as necessary.
6. Check voltage between oil level module connector terminal No. 10 (Orange wire) and ground. If battery voltage is present, go to next step. If battery voltage is not present, check for blown fuse No. 9C (10-amp) in instrument panel fuse block. Also check for open, high resistance or short to ground in Orange wire. Repair or replace as necessary.
7. Check voltage between oil level module connector terminals No. 10 (Orange wire) and No. 5 (Black or Black/White wire). If battery voltage is present, check for poor connections at oil level module. If connections are okay, replace oil level module. If battery voltage is not present, check for open or high resistance in Black/White wire. Repair or replace as necessary.

TACHOMETER TEST

1. Turn ignition off. Disconnect Electronic Ignition (EI) module connector. Plug Gauge Tester (J-33431) into a wall outlet. Connect Harness Adapter (J-33431-10) to tester. Connect adapter Black wire to ground. Connect adapter Red wire to EI module connector terminal "E" (White wire). Set tester to 54 Mph (60 Hz), and turn power switch on. Turn ignition on. If tachometer reads about 1350 RPM, check EI module connector for good terminal contact. If terminal contact is okay, replace EI module.
2. If tachometer does not read 1350 RPM, check White wire for an open circuit or short to ground. Check all connectors and instrument cluster connector for good terminal contact. If all circuits are okay, replace instrument cluster.

1. Turn ignition off. Disconnect oil pressure sensor/switch connector. Connect 2 Red wires from Gauge Tester (J-33431) to terminals "A" (Tan wire) and "B" (Black/White wire). Turn ignition on. Set tester resistance dials to zero ohms, then to 90 ohms. If tester displays zero psi at zero ohms, then 80 psi at 90 ohms, check oil pressure sensor/switch connector for good terminal contact. If terminal contact is okay, replace oil pressure sensor/switch.
2. If tester does not display zero psi at zero ohms, then 80 psi at 90 ohms, check Tan and Black/White wires for an open circuit or resistance. Check all connectors for good terminal contact. If all circuits are okay, replace instrument cluster.

HEADLIGHT SWITCH

With headlights off, battery voltage should be present at headlight switch/lamp control module terminals "H" (Orange wire) and "E" (Red wire). With headlights on, battery voltage should also be present at terminals "H" (Black/White wire) and "A" (Black/White wire). If voltage is not as specified, check wiring. If voltage is as specified, replace switch.

REMOVAL & INSTALLATION

Disconnect negative battery cable. Remove sound insulators and instrument panel lower trim pad. Remove rubber collar from steering column. (Scheme 2) Remove gear selector clip from steering column. Remove 4 bolts from IPC and pull IPC straight out. To install, reverse removal procedure. Tighten bolts to 14 INCH lbs. (1.5 N.m).

Scheme 2

See also:
• TESTS W/CODES
• COMPUTER RELEARN PROCEDURES