Fuel module reservoir assembly: fuel pump wire connectors may overheat - recall 05V-155

Why it happensThe fuel module reservoir assemblies contain fuel pump wire connectors that may overheat under certain operating conditions.

CERTAIN TRUCKS AND SPORT UTILITY VEHICLES WERE BUILT WITH FUEL MODULE RESERVOIR ASSEMBLIES THAT CONTAIN FUEL PUMP WIRES CONNECTORS MAY OVERHEAT UNDER CERTAIN OPERATING CONDITIONS.— [1]

If leftIf the ignition circuit wire is exposed, the fuel pump fuse blows, disabling the pump and causing a stall or no-start.

IF THE IGNITION CIRCUIT WIRE IS EXPOSED, THE FUEL PUMP FUSE WILL BLOW, DISABLING THE FUEL PUMP AND CAUSING AN ENGINE STALL OR NO-START CONDITION.— [1]

If leftEnough heat at the pass-through connector may make a hole in it, which may light the 'Service Engine Soon' light during the emission system diagnostic routine.

IF SUFFICIENT HEAT IS CONDUCTED TO THE PASS-THROUGH CONNECTOR, A HOLE IN THE CONNECTOR MAY RESULT, WHICH MAY CAUSE A 'SERVICE ENGINE SOON' LIGHT TO BE ILLUMINATED DURING THE EMISSION SYSTEM DIAGNOSTIC ROUTINE.— [1]

If leftFuel vapor and in some cases liquid fuel may leak from the tank through the hole in the connector body.

FUEL VAPOR AND IN SOME CASES LIQUID FUEL MAY LEAK OUT OF THE FUEL TANK THROUGH THE HOLE IN THE CONNECTOR BODY.— [1]

If leftFuel leakage in the presence of an ignition source could result in a fire.

FUEL LEAKAGE, IN THE PRESENCE OF AN IGNITION SOURCE, COULD RESULT IN A FIRE.— [1]

If leftIf the ignition circuit or ground wire is exposed and shorts to the fuel level sender card wires, fuel level readings may be inaccurate.

ALSO IF THE IGNITION CIRCUIT OR GROUND WIRE IS EXPOSED AND SHORTS TO THE FUEL LEVEL SENDER CARD WIRES, INACCURATE FUEL LEVEL READINGS MAY RESULT.— [1]

RepairDealers remove the fuel tank and the module reservoir assemblies and install a new service kit.

DEALERS WILL REMOVE THE FUEL TANK, AND REMOVE THE MODULE RESERVOIR ASSEMBLIES FROM THE TANK, AND INSTALL A NEW SERVICE KIT FREE OF CHARGE.— [1]

Applies toRecall bulletin 05-027 is being prepared to cover the 2000-01 Chevrolet Suburban and GMC Yukon XL (excluding 2500 HD).

A recall bulletin 05-027 is being prepared to cover 2000-01 Chevrolet Suburban and GMC Yukon XL (excluding 2500 HD).— [2]

Why it happensThe terminals in the 4-wire electrical connector at the top of the fuel pump assembly may suffer fretting and high resistance.

The terminals in the 4-wire electrical connector at the top of the fuel pump assembly may experience fretting and high resistance.— [2]

RepairThe bulletin explains how to install repair kit 15824379 on the fuel pump assembly; the kit contains replacement electrical connectors, a replacement fuel level sensor, related hardware and instructions.

The bulletin explains how to install a repair kit 15824379 to the fuel pump assembly. It contains replacement electrical connectors, a replacement fuel level sensor, related hardware and instructions.— [2]

RepairInstalling the replacement connector components in the cover is a new procedure; the fuel level sensor is replaced by the existing SI procedure, but the float assembly is re-used, which is new.

Installing replacement connector components in the cover is a new procedure. The kit installation also requires replacing the fuel level sensor, which is an existing SI procedure. However, in this repair, you will re-use the float assembly, which is a new procedure.— [2]

RepairRemove and discard the fuel pump fuse as instructed; a replacement is in the kit, and using a new fuse is a precaution.

TIP: You are instructed to remove and discard the fuel pump fuse. A replacement is included in the kit. Using a new fuse is a precaution.— [2]

RepairAlign the connector with the opening in the cover, then press it into place with finger pressure until the tab clicks.

IMPORTANT: Be sure the connector is properly aligned with the opening in the cover, then use finger pressure to install the connector into place until the tab clicks.— [2]

RepairTo remove the float arm from the old fuel level sensor, twist a small screwdriver under the float arm to push the arm from the retainers.

TIP: When removing the float arm from the old fuel level sensor, twist a small screwdriver under the float arm, which will push the arm from the retainers— [2]

RepairCut the old 4-pin MetriPack 150 connector from the vehicle harness for the new chassis connector, staggering the cuts by 1.5 inches (40 mm) so the splices do not overlap.

You need to cut the old 4-pin MetriPack 150 connector from the harness to prepare the vehicle harness for the new chassis electrical connector. IMPORTANT: Stagger the cuts by 1.5 inches (40 mm) so the splices will not overlap— [2]

RepairMatch the wire colors and splice the new 4-pin GT 280 connector to the vehicle harness; the blue splices are for the black and grey wires and the red splices for the purple and orange/black wires.

Match the wire colors and splice the new 4-pin GT 280 connector to the vehicle harness. TIP: There are two colors of splices in the kit. The blue splices are for the black and grey wires, and the red splices are for the purple and orange/black wires.— [2]

CautionAfter removing the connector, be sure the O-ring does not remain in the cover.

TIP: After removing the connector, be sure the O-ring does not remain in the cover— [2]

CautionBe sure the O-ring is properly seated on the connector and lubricated with the oil in the kit; an O-ring that is not properly lubricated may be damaged during installation.

- Be sure the O-ring is properly seated on the connector and properly lubricated using the oil in the kit (fig. 6) . IMPORTANT: The O-ring may be damaged during installation if it is not properly lubricated.— [2]

CautionBe sure the sensor wires are routed through their retainers so that they do not interfere with the float arm.

IMPORTANT: Be sure the sensor wires are properly routed through their retainers so they do not interfere with float arm operation.— [2]

Applies toIn a letter dated April 14, 2005, GM notified ODI of a safety defect in approximately 316,508 MY 2000-01 1500 series Chevrolet Suburban and GMC Yukon XL vehicles (recall 05V-155).

In a letter dated April 14, 2005, General Motors (GM) notified ODI that it had identified a defect related to motor vehicle safety in approximately 316,508 model year (MY) 2000-01 1500 series Chevrolet Suburban and GMC Yukon XL vehicles (recall 05V-155).— [3]

First signsODI has received 10 complaints alleging fuel tank leakage or engine stall due to fuel pump wiring failure: six allege that fuel pump wiring overheated and melted the plastic connector, resulting in fuel leakage from the top of the fuel tank assembly, and four allege that fuel pump wiring failure caused an engine stall incident.

ODI has received 10 complaints alleging fuel tank leakage or engine stall due to fuel pump wiring failure. Six of the complaints allege that fuel pump wiring overheated and melted the plastic connector, resulting in fuel leakage from the top of the fuel tank assembly. Four complaints allege that fuel pump wiring failure caused an engine stall incident.— [4]

First signsThe fuel pump wiring and connector may overheat and melt a hole in the top of the fuel pump module; possible consequences include fuel tank leakage and engine stall with no restart.

The fuel pump wiring and connector may overheat and melt a hole in the top of the fuel pump module. Possible consequences include fuel tank leakage and engine stall with no restart.— [4]

How to confirmOn-board emissions diagnostics may detect holes of approximately 0.040 inches (= 1.02 mm) or more and set a service engine soon warning light. The connector sits below the fuel level when the tank is full.

On-board emissions diagnostics may detect holes that are approximately 0.040 inches or more and set a service engine soon warning light. The connector position in the subject vehicles is below the fuel level when the tank is full.— [3]

If leftEngine stall can occur if bare wire exposed by melted insulation shorts against a ground or ground wire and the fuel pump relay fuse blows, or if the vehicle runs out of fuel because a short between the fuel pump wiring and the level sensor wiring makes the fuel gauge read inaccurately.

Engine stall can occur if: (1) a short occurs in the pump wiring (bare wire exposed by melted insulation shorts against a ground or ground wire) and the fuel pump relay fuse is blown; or (2) the vehicle runs out of fuel due to an inaccurate fuel gauge reading resulting from an electrical short between the fuel pump wiring and the level sensor wiring.— [3]

Why it happensGM's analysis of five assemblies returned from incident vehicles determined that the condition is caused by elevated resistance/arcing at the MRA undercover B cavity terminal of the four-way 150 metri-pak connector, which GM attributes to a depressed contact arm at the 150 metri-pak B cavity female terminal. GM is continuing its investigation to complete its root cause analysis.

GM's analysis of five assemblies returned from incident vehicles determined that the condition is caused by elevated resistance/ arcing at the MRA undercover B cavity terminal of the four-way 150 metri-pak connector. GM attributes the high resistance and arcing to a depressed contact arm at the 150 metri-pak B cavity female terminal. Gm is continuing its investigation to complete its root cause analysis.— [3]

Why it happensGM's analysis identified the cause of the overheated wiring as a high-resistance condition in the MRA connector contacts due to fretting corrosion that may develop over time. The corrosion is caused by movement between the contact surfaces, influenced primarily by chassis and fuel tank vibration characteristics.

GM's analysis identified the cause of the overheated wiring as a high-resistance condition in the MRA connector contacts due to fretting corrosion that may develop over time. GM determined that the corrosion is caused by movement between the contact surfaces and that such movement is primarily influenced by chassis and fuel tank vibration characteristics.— [3]

Why it happensGM's testing found that the fuel tank vibration of the recalled MY 2000-01 1500-series vehicles was significantly greater than in other GM vehicles equipped with the same MRA connectors.

GM's testing found that the fuel tank vibration characteristics of the recalled MY 2000-01 1500-series vehicles were significantly greater than in other GM vehicles equipped with the same MRA connectors.— [3]

CautionA survey conducted by GM found evidence of MRA wiring over-heating in almost one-third of the 1500-series vehicles inspected.

These vehicles had the highest rate of related fuel leak and stall complaints; and a recent survey conducted by GM found evidence of MRA wiring over-heating in almost one-third of the 1500-series vehicles inspected.— [3]

Applies toThe same MRA connector is also fitted to approximately 33,000 MY 2000-01 2500-series Suburban and Yukon XL vehicles, to short wheelbase Yukon and Tahoe utility vehicles and to full-size Silverado and Sierra pickup trucks.

Other vehicles equipped with the subject MRA connector and evaluated during this investigation include approximately 33,000 MY 2000-01 2500-series Sububran and Yukon XL vehicles, which fall within the scope of EA04-026, and peer populations of short wheelbase Yukon and Tahoe utility vehicles and full-size Silverado and Sierra pickup trucks.— [3]

Applies toThose vehicles are not included in recall 05V-155: their fuel tanks vibrate significantly less at the MRA interface, no fuel leakage due to overheated wiring was verified in the pickups and short-wheelbase utilities, and there were only three potentially related leakage complaints in the 2500-series. GM's survey found no overheated wiring in the 2500-series and pickups inspected, and a rate in the short-wheelbase utilities lower than the recalled vehicles by an order of magnitude.

These vehicles are not included in recall 05V-155 for the following reasons: (1) these vehicles are equipped with fuel tanks with significantly less vibration at the MRA interface than the recalled vehicles; (2) the potential for fuel leakage is substantially lower in the pickup trucks and short-wheelbase utility vehicles due to differences in fuel tank configuration and no incidents of fuel leakage due to overheated wiring were verified in these vehicles; (3) there have been only three potentially related complaints of fuel leakage associated with the overheated wiring condition in the 2500-series long- wheelbase utility vehicles; and (4) no evidence of overheated wiring was found in the 2500-series Suburban and Yukon XL vehicles and pickup trucks inspected by GM in its vehicle survey efforts and the rate found in the short-wheelbase utilities was lower than the recalled vehicles by an order of magnitude.— [3]

Applies toModular reservoir assemblies with the 150 metri-pak connectors were used in several million C/K-series sport utility vehicles and pickup trucks from MY 1997 through 2002, when GM released a metal MRA cover and a 280 metri-pak connector in the subject vehicles.

Modular reservoir assemblies using the 150 metri-pak connectors were used by GM in several million c/k-series sport utility vehicles and pickup trucks from MY 1997 through 2002, when GM released a metal MRA cover and a 280 metri- pak connector in the subject vehicles.— [3]

CautionODI will continue to monitor the experience in the 2500 series MY 2000-01 long-wheelbase utility vehicles; the closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists for the 2500 series vehicles.

ODI will continue to monitor the experience in the 2500 series MY 2000-01 long-wheelbase utility vehicles. The closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists for the 2500 series vehicles.— [3]