INFORMATION ON OBTAINING DIAGNOSTIC ASSISTANCE. GMC Truck Sonoma Pickup

THIS BULLETIN IS BEING REVISED TO INFORM "NAES" DEALERS THAT THEY ARE NOT AUTHORIZED TO UTILIZE THIS SERVICE BULLETIN.

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"NAES" DEALERS ARE NOT AUTHORIZED TO UTILIZE THIS SERVICE BULLETIN.

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REVISION: 08/30/94

THIS BULLETIN IS BEING REVISED TO CORRECT THE GM OF CANADA "800" PHONE NUMBERS. PLEASE DISCARD BULLETIN 476512 (GROUP REFERENCE 6E - ENGINE FUEL & EMISSION). ----------------------------------------------------------------------

REVISED: 10/18/94

THIS BULLETIN IS BEING REVISED TO CHANGE DTC INFORMATION AND TO ADD WARRANTY INFORMATION. PLEASE DISCARD BULLETIN 476512 (GROUP REFERENCE 6E - ENGINE FUEL & EMISSION). ---------------------------------------------------------------------- REVISED: 10/26/94

SUBJECT: INFORMATION ON USE OF DIVISIONAL TECH ASSIST FOR OBD II DIAGNOSTIC ASSISTANCE

MODELS: 1995 S/T TRUCKS WITH OBD II (ON BOARD DIAGNOSTICS II), A 4.3L ENGINE (VIN W - RPO L35) AND HYDRA-MATIC 4L60-E TRANSMISSION (M30)

VEHICLE APPLICATIONS: 1995 S/T--TRUCKS WITH 4.3L (L35) ENGINE AND A HYDRA-MATIC 4L60-E TRANSMISSION (M30)

THE NEW OBD II (ON BOARD DIAGNOSTICS II) SYSTEM HAS BEEN INSTALLED ON SOME 1995 S/T TRUCKS EQUIPPED WITH THE 4.3L (L35) ENGINE, AND WILL BE EXPANDED TO ALL GM VEHICLES BY 1996. THE GENERAL MOTORS POWERTRAIN GROUP IS ASKING FOR YOUR ASSISTANCE TO ENSURE THIS NEW DIAGNOSTIC SYSTEM ENHANCES SERVICEABILITY OF GM VEHICLES.

DIVISIONAL TECHNICAL ASSISTANCE SHOULD BE CALLED FOR SERVICE ASSISTANCE, AS WELL AS REPAIR FEEDBACK.

**CHEVROLET 1-800-227-3175 FOR ENGINES AND DRIVETRAIN** **GMC 1-800-832-3646 FOR ENGINES** **GMC 1-800-832-2953 FOR DRIVETRAIN (TRANSMISSIONS)**

**GM OF CANADA CALL 1-800-263-7740 (ENGLISH)** **1-800-263-7960 (FRENCH)**

FROM A TOUCH-TONE MENU, PRESS 3 FOR FUEL AND EMISSIONS.

THE OBD II HELP LINE SHOULD BE CALLED FOR ALL OBD II REPAIRS. TECHNICIANS ARE ENCOURAGED TO ATTEMPT SERVICE OF THE VEHICLE ACCORDING TO THE SERVICE MANUAL PROCEDURES PRIOR TO CALLING. THE OBD II TECHNICAL OPERATOR WILL INTERVIEW THE SERVICING TECHNICIAN TO IDENTIFY SUCH CONCERNS AS SERVICE MANUAL DIAGNOSTIC FLOW CHART, WHAT CODE WAS SET, WHAT REPAIR FIXED THE PROBLEM, ETC. THE DTC SUMMARY SHEET SHOULD BE FILLED OUT WITH ALL NECESSARY INFORMATION PRIOR TO CALLING THE OBD II TECHNICAL ASSISTANCE NUMBER.

REMINDER: A TECH 1 OBD II APPLICATION KIT (P/N 7000041) WILL BE NEEDED TO PERMIT THE TECH 1 OR TECH 1 SERIES A TO COMMUNICATE WITH OBD II AND NON-OBD II VEHICLES EQUIPPED WITH THE 16 PIN DLC. IT WILL BE NECESSARY TO UPDATE YOUR TECH 1 MASS STORAGE CARTRIDGE WITH THE JUNE, 1994 OR LATER TECHLINE CD-ROM PRIOR TO OPERATING THIS KIT.

THE FOLLOWING ARE DIAGNOSTIC TROUBLE CODES FOR OBD II.

P0106 MAP SENSOR RANGE/RATIONALITY P0107 MAP SENSOR CIRCUIT-LOW INPUT P0108 MAP SENSOR CIRCUIT-HIGH INPUT P0112 INTAKE AIR TEMP. SENSOR CIRCUIT-LOW INPUT P0113 INTAKE AIR TEMP. SENSOR CIRCUIT-HIGH INPUT P0117 ENGINE COOLANT TEMP. SENSOR CIRCUIT-LOW INPUT P0118 ENGINE COOLANT TEMP. SENSOR CIRCUIT-HIGH INPUT P0121 THROTTLE POSITION SENSOR CIRCUIT-RANGE/RATIONALITY P0122 THROTTLE POSITION SENSOR CIRCUIT-LOW INPUT P0123 THROTTLE POSITION SENSOR CIRCUIT-HIGH INPUT P0125 MIN. COOL TEMP. TO AFLOW C.L. OP. NOT ACHIEVED WITHOUT EXCESS. TIME P0131 OS2 CIRCUIT-LOW VOLTAGE (BANK 1, SENSOR 1) P0132 OS2 CIRCUIT-HIGH VOLTAGE (BANK 1, SENSOR 1) P0133 OS2 SENSOR CIRCUIT-SLOW RESPONSE (BANK 1, SENSOR 1) P0134 OS2 CIRCUIT-NO ACTIVITY DETECTED (BANK 1, SENSOR 1) P0135 OS2 HEATER CIRCUIT MALFUNCTION (BANK 1, SENSOR 1) P0137 OS2 CIRCUIT-LOW VOLTAGE (BANK 1, SENSOR 2) P0138 OS2 CIRCUIT-HIGH VOLTAGE (BANK 1, SENSOR 2) P0140 OS2 CIRCUIT-NO ACTIVITY DETECTED (BANK 1, SENSOR 2) P0141 OS2 HEATER CIRCUIT MALFUNCTION (BANK 1, SENSOR 2) P0171 SYSTEM TOO LEAN (BANK 1) P0172 SYSTEM TOO RICH (BANK 1) P0300 RANDOM MISFIRE DETECTED P0301 CYLINDER 1 MISFIRE DETECTED P0302 CYLINDER 2 MISFIRE DETECTED P0303 CYLINDER 3 MISFIRE DETECTED P0304 CYLINDER 4 MISFIRE DETECTED P0305 CYLINDER 5 MISFIRE DETECTED P0306 CYLINDER 6 MISFIRE DETECTED P0325 KNOCK SENSOR CIRCUIT MALFUNCTION P0326 KNOCK SENSOR CIRCUIT-RANGE P0337 CRANKSHAFT POSITION SENSOR CIRCUIT-LOW INPUT P0338 CRANKSHAFT POSITION SENSOR CIRCUIT-HIGH INPUT P0340 CAMSHAFT POSITION SENSOR CIRCUIT MALFUNCTION P0341 CAMSHAFT POSITION SENSOR CIRCUIT RANGE/RATIONALITY P0401 EXHAUST GAS RECIRCULATION-INSUFFICIENT FLOW DETECTED P0420 CATALYST SYSTEM EFFICIENCY BELOW A THRESHOLD (BANK 1) P0441 EVAP. EMISSION CONTROL SYSTEM INCORRECT PURGE FLOW P0500 VEHICLE SPEED (VS) SENSOR SIGNAL MISSING P0506 IDLE CONTROL SYSTEM RPM LOWER THAN EXPECTED P0507 IDLE CONTROL SYSTEM RPM HIGHER THAN EXPECTED

P1106 MAP SENSOR CIRCUIT-HIGH INPUT (INTERMITTENT) P1107 MAP SENSOR CIRCUIT-LOW INPUT (INTERMITTENT) P1111 INTAKE AIR TEMP. SENSOR CIRCUIT-HIGH INPUT (INTERMITTENT) P1112 INTAKE AIR TEMP. SENSOR CIRCUIT-LOW INPUT (INTERMITTENT) P1114 ENGINE COOLANT TEMP. SENSOR CIRCUIT-LOW INPUT (INTERMITTENT) P1115 ENGINE COOLANT TEMP. SENSOR CIRCUIT-HIGH INPUT (INTERMITTENT) P1121 THROTTLE POSITION SENSOR CIRCUIT-HIGH INPUT (INTERMITTENT) P1122 THROTTLE POSITION SENSOR CIRCUIT-LOW INPUT (INTERMITTENT) P1221 FUEL PUMP SECONDARY CIRCUIT LOW P1345 CAMSHAFT SENSOR MISINSTALLED P1351 EST OUTPUT HIGH P1361 EST NOT TOGGLING AFTER ENABLE P1406 EXHAUST GAS RECIRCULATION SYSTEM-PINTLE POSITION ERROR P1441 EVAP. EMISSION CONTROL SYSTEM-CONTINUOUS OPEN PURGE FLOW P1442 PURGE SOLENOID DIAGNOSTIC VACUUM SWITCH MALFUNCTION P1508 IDLE AIR CONTROL-LOW P1509 IDLE AIR CONTROL-HIGH

P0502 VEHICLE SPEED SENSOR SIGNAL LOW P0503 VEHICLE SPEED SENSOR INTERMITTENT P0560 SYSTEM VOLTAGE MALFUNCTION (SYSTEM VOLTAGE LOW) P0703 BRAKE SWITCH INPUT MALFUNCTION P0712 TRANSMISSION FLUID TEMP SENSOR CIRCUIT (HIGH) P0713 TRANSMISSION FLUID TEMP SENSOR CIRCUIT (LOW) P0742 TCC STUCK "ON" P0748 PRESSURE CONTROL SOLENOID CURRENT P0753 1-2 (A) SHIFT SOLENOID ELECTRICAL P0756 2-3 (B) SHIFT SOLENOID PERFORMANCE P0758 2-3 (B) SHIFT SOLENOID ELECTRICAL P1810 PRESSURE SWITCH ASSEMBLY CIRCUIT MALFUNCTION WITHOUT AN OUTPUT SPEED P1812 TRANSMISSION FLUID OVERTEMP P1860 TCC PWM SOLENOID ELECTRICAL P1864 TCC SOLENOID ELECTRICAL P1870 TRANSMISSION COMPONENT SLIPPING P1886 3-2 CONTROL SOLENOID CIRCUIT FAULT

TO HELP MAKE THIS PROGRAM SUCCESSFUL, DEALERS WILL BE COMPENSATED FOR THE EXTRA EFFORT AND TIME SPENT AS EXPLAINED IN THIS LETTER. THE OBD II TECHNICAL OPERATOR WILL PROVIDE INSTRUCTIONS ALLOWING THE DEALER TO SUBMIT FOR REIMBURSEMENT OF ALL EXPENSES. THESE REIMBURSEMENTS ARE IN ADDITION TO THE NORMAL WARRANTY COMPENSATIONS FOR DIAGNOSIS AND REPAIR.

FOR EVERY OBD II TECHNICAL ASSISTANCE CALL MADE (MAXIMUM ONE CALL PER VEHICLE SERVICED) DEALERS WILL BE REIMBURSED 0.3 HOURS. THE OBD II TECHNICAL OPERATOR MAY REQUEST THE RETURN OF A PART(S) REPLACED DURING THE REPAIR. IN THESE INSTANCES, IN ADDITION TO THE 0.3 HOURS TELEPHONE REIMBURSEMENT, 0.2 HOURS SHOULD BE ADDED FOR EACH PART RETURNED, ALONG WITH THE ACTUAL FREIGHT CHARGES INCURRED TO RETURN THE PART(S).

THE DTC SUMMARY SHEET SHOULD BE FILLED OUT WILL ALL NECESSARY INFORMATION PRIOR TO CALLING THE OBD II TECHNICAL ASSISTANCE NUMBER.

WARRANTY INFORMATION:

LABOR OPERATION NUMBER: Z7600 LABOR TIME INFORMATION: 0.3 HR. FOR TECHNICAL ASSISTANCE CONTACT 0.2 HR. ADDED FOR EACH PART RETURNED

FAILURE CODE: 92 CUSTOMER COMPLAINT CODE: OS

ENTER TIME IN LABOR HOURS. A TOTAL OF .5 HRS. IS AVAILABLE FOR DEALERS THAT CONTACT TECHNICAL ASSISTANCE AND ARE REQUESTED TO RETURN A PART. SHIPPING AND/OR CORE CHARGES ARE TO BE ENTERED AS NET AMOUNT. THE ACTUAL REPAIR IS TO BE SUBMITTED USING THE APPROPRIATE LABOR TIME GUIDE OPERATION AND TIME ALLOWANCE.

FIGURES: 0 ATTACHMENTS: 1

Object Number: 85150 Size: FS

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER." THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS OCCURRING ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.