Home/Buick/Electra/Buick Electra VI (1985-1990)/Repair manual/Tests W/codes - 3.0l VIN (l) & 3.8l VIN (3 & 7)/DIAGNOSTIC TROUBLE CODE IDENTIFICATION

Contents

Section: Tests W/codes - 3.0l VIN (l) & 3.8l VIN (3 & 7)

MODEL IDENTIFICATION

DESCRIPTION & OPERATION

DIAGNOSTIC SYSTEM OPERATION

"HARD FAILURES"

"INTERMITTENT FAILURES"

BASIC DIAGNOSTIC PROCEDURE

READING TROUBLE CODES

ECM TROUBLE CODE DEFINITIONS

TROUBLE CODE DETERMINATION (HARD OR INTERMITTENT)

CLEARING TROUBLE CODES

DIAGNOSTIC MATERIALS

Diagnostic Charts

Diagnostic Aids

FIELD SERVICE MODE CHECK (FUEL INJECTED MODELS)

SPECIAL DIAGNOSTIC TOOLS

SCAN TESTER USAGE

SCAN TESTER - TEST DATA PARAMETERS

DIAGNOSTIC CONNECTOR LOCATION

DIAGNOSTIC CIRCUIT CHECK

"SCAN" DIAGNOSTIC CIRCUIT CHECK

DIAGNOSTIC TROUBLE CODE IDENTIFICATION

CHART A1 - NO "SERVICE ENGINE SOON" LIGHT

Won't Flash Code 12 "Service Engine Soon" ("SES") Light On

CHART A3 - ENGINE CRANKS BUT WILL NOT RUN (3.0L VIN L)

Circuit Description For Steps 1-6 (1 Of 3, 3.0L VIN L)

Circuit Description For Steps 7-11 (2 Of 3, 3.0L VIN L)

Circuit Description For Steps 12 & 13 (3 Of 3, 3.0L VIN L)

Engine Cranks But Won't Run (3.8L Non-Turbo With Type I Ignition System)

Ignition System Identification

Circuit Description For Steps 1-6 (1 Of 3, 3.8L Non-Turbo With Type I Ignition System)

Circuit Description For Steps 7-11 (2 Of 3, 3.8L Non-Turbo With Type I Ignition System)

Circuit Description For Steps 12-14 (3 Of 3, 3.8L Non-Turbo With Type I Ignition System)

Engine Cranks But Won't Run (1 Of 3, 3.8L Non-Turbo W/ Type II Ignition System)

Circuit Description For Steps 1-6 (1 Of 3, Type II Ignition)

Circuit Description For Steps 7-11 (2 Of 3, 3.8L Non-Turbo With Type II Ignition System)

Circuit Description - Steps 12-14 (3 Of 3, 3.8L Non-Turbo With Type II Ignition System)

CHART A3 - ENGINE CRANKS BUT WON'T RUN (3.8L TURBO)

CHART A5 - FUEL SYSTEM ELECT. TEST (3.0L VIN L, "N" BODY)

CHART A5 - FUEL SYSTEM ELECTRICAL TEST (3.8L)

CHART A7 - FUEL PRESSURE TEST - ALL ENGINES

CHART B1 - RESTRICTED EXHAUST SYSTEM CHECK

Check At Air Pipe

Check At O2 Sensor

Diagnosis

CHART C1 - ECM REPLACEMENT CHECK CHART

CHART C1A - PARK/NEUTRAL SWITCH

CHART C1E - POWER STEERING PRESSURE SWITCH CHECK

CHART C2A - INJECTOR BALANCE TEST

CHART C2C - IDLE AIR CONTROL

CHART C3 - CANISTER PURGE CHECK

CHART C4E - 3.8L TYPE I IGNITION

CHART C4F - 3.8L TYPE II IGNITION

Test Description For Steps 1-5 (3.0L VIN L)

Test Description For Steps 1-5 (3.8L VIN's 3 & 7)

Test Description For Steps 1-4 (3.0L VIN L & 3.8L VIN's 3 & 7)

CHART C4G - 3.8L TYPE I TURBO IGNITION

CHART C5 - ELECTRONIC SPARK CONTROL

CHART C7 - EXHAUST GAS RECIRCULATION

CHART C8 - TORQUE CONVERTER CLUTCH (3.0L "N" BODY)

Torque Converter Clutch (TCC) (3.8L Non-Turbo, "A", "C", & H" Bodies)

Torque Converter Clutch (TCC) (3.8L Turbo "G" Body)

CHART C10A - A/C CLUTCH (3.0L & 3.8L NON-TURBO)

CHART C10D - A/C CLUTCH CONTROL (3.8L TURBO "G" BODY)

CHART C10E - A/C CLUTCH CONTROL (3.8L TURBO "G" BODY)

Chart C12A - Coolant Fan Check (3.0L VIN L, "N" Body)

Chart C12B - Fan On At All Times (3.0L VIN L, "N" Body)

Chart C12C - No Low Speed Fan (3.0L Vin L, "N" Body)

Chart C12A - Coolant Fan Check (1 Of 3, All 3.8L Except 3.8L Turbo "G" Body)

Chart C12B - Fan Always On (2 Of 3, All 3.8L Except 3.8L Turbo "G" Body)

Chart C12C - No Low Speed Fan (3 Of 3, All 3.8L Except 3.8L Turbo "G" Body)

Chart C12A - 2-Speed Coolant Fan Check (3.8L Turbo "G" Body)

Chart C12B - Fan On At All Times (3.8L Turbo "G" Body)

Chart C12C - No Low Speed Fan (3.8L Turbo "G" Body)

Chart C12D - Coolant Fan Check (1 Of 3, A/C Equipped W/O Heavy Duty Cooling - 3.8L "A" Body)

Chart C12E - Coolant Fan Check (2 Of 3, A/C Equipped W/O Heavy Duty Cooling - 3.8L "A" Body)

Chart C12F - Coolant Fan Check (3 Of 3, A/C Equipped W/O Heavy Duty Cooling - 3.8L "A" Body)

Chart C12G - Coolant Fan On At All Times (A/C Equipped W/O Heavy Duty Cooling - 3.8L "A" Body)

Chart C12H - Coolant Fan Check (1 Of 3, A/C Equipped W/Heavy Duty Cooling - 3.8L "A" Body)

Chart C12I - Coolant Fan Check (2 Of 3, A/C Equipped W/Heavy Duty Cooling - 3.8L "A" Body)

Chart C12J - Coolant Fan Check (3 Of 3, A/C Equipped W/Heavy Duty Cooling - 3.8L "A" Body)

Chart C12K - Coolant Fan On At All Times (A/C Equipped W/Heavy Duty Cooling - 3.8L "A" Body)

CODE 13 - OPEN OXYGEN (O2) SENSOR CIRCUIT

Coolant Temperature Sensor (CTS) Signal Voltage Low

Coolant Temperature Sensor (CTS) Signal Voltage High

CODE 21 - THROTTLE POSITION SENSOR SIGNAL VOLTAGE HIGH

Throttle Position Sensor (TPS) Signal Voltage Low

Manifold Air Temperature (MAT) Sensor Signal Voltage High

CODE 24 - VEHICLE SPEED SENSOR

Manifold Air Temperature (MAT) Sensor Signal Voltage Low

CODE 31 - WASTEGATE SOLENOID (3.8L TURBO "G" BODY)

CODE 32 - EGR VACUUM CONTROL CIRCUIT

CODE 33 - MASS AIRFLOW (MAF) SENSOR

CODE 34 - MASS AIRFLOW (MAF) SENSOR

Cam Sensor Signal (3.8L Non-Turbo VIN 3 & 3.8L Turbo VIN 7)

CODE 42 - EST IGNITION CIRCUIT

CODE 43 - ELECTRONIC SPARK CONTROL

CODE 44 - LEAN EXHAUST INDICATION

CODE 45 - RICH EXHAUST INDICATION

CODE 51 - PROM ERROR (FAULTY OR INCORRECT PROM)

CODE 52 - CALPAK ERROR (FAULTY OR INCORRECT CALPAK)

CODE 55 ECM ERROR

All sections

DIAGNOSTIC TROUBLE CODE IDENTIFICATION Buick Electra VI

Tests W/codes - 3.0l VIN (l) & 3.8l VIN (3 & 7)

DIAGNOSTIC TROUBLE CODE IDENTIFICATION

DTC	Description
13	Open Oxygen (O2) Sensor Circuit
14	CTS Signal Voltage Low
14	CTS Signal Voltage High
21	Throttle Position Sensor Signal Voltage High
22	TPS Signal Voltage Low
23	MAT Sensor Signal Voltage High
24	Vehicle Speed Sensor
25	MAT Sensor Signal Voltage Low
31	Wastegate Solenoid (3.8L Turbo "G" Body)
32	EGR Vacuum Control Circuit
33	MASS Airflow (MAF) Sensor
34	MASS Airflow (MAF) Sensor
41	Cam Sensor Signal (3.8L Vins 3 & 7)
42	EST Ignition Circuit
43	Electronic Spark Control
44	Lean Exhaust Indication
45	Rich Exhaust Indication
51	PROM ERROR (Faulty Or Incorrect PROM)
52	CALPAK Error (Faulty Or Incorrect CALPAK)
55	ECM Error

DIAGNOSTIC TROUBLE CODE IDENTIFICATION