PE99073 · PE
ELECTRICAL SYSTEM Investigation
ODI HAS RECEIVED 21 COMPLAINTS WHERE OWNERS ALLEGE THAT THE STANDARD GM FACTORY SUPPLIED AC DELCO BATTERY CASE FAILED, RESULTING IN THE LEAKAGE OF SULFURIC ACID.OF THE 21 COMPLAINT VEHICLES, SIX SUBURBAN, THREE TAHOES, AND ONE YUKON OWNER(S) COMPLAINED ABOUT A LOSS OF BRAKE FLUID FROM DETERIORATION OF THE RIGHT FRONTBRAKE LINE AS A RESULT OF SULFURIC ACID CONTAMINATION.THE REMAINING 11 COMPLAINTS PERTAIN PRIMARILY TO SULFURIC ACID LEAKAGE FROM THE BATTERY CASE.AT LEAST ONE COMPLAINANT STATED THAT THE REPLACEMENT BATTERY ALSO FAILED.SEVERAL OF THE COMPLAINANTS NOTE THAT THE LEAKING ACID HAD COME IN CONTACT WITH A WIRE HARNESS AT THE FRAME IN THE VICINITY OF THE STEEL BRAKE LINE.A FIELD INSPECTION BY ODI INDICATES THAT THE DESCRIBED HARNESS IS THE ABS CONNECTION TO THE RIGHT FRONT WHEEL SPEED SENSOR.PRIOR TO THE BATTERY CASE FAILURE, THERE IS USUALLY NO WARNING (SHORT OF AN UNDERHOOD INSPECTION), AND THE ENSURING DAMAGE (SULFURIC ACID CONTAMINATION) IS PROGRESSIVE.OF THE KNOWN BATTERY FAILURES, THERE MAY BE A TEMPERATURE CORRELATION, AS 60% OF THE OWNER COMPLAINTS CAME FROM FOUR STATES; CALIFORNIA, FLORIDA, GEORGIA AND TEXAS.THERE IS ALSO A PRODUCT IMPROVEMENT PROGRAM AND ENGINEERING CHANGE NOTICE TO ADD 1% SILVER TO THE BATTERY'S POSITIVE SIDE TERMINALL, WITH THE EARLIEST IMPLEMENTATION DATE FOR THIS BEING FEB 2, 1998.THE EFFECT OF THIS DESIGN CHANGE IS AS YET UNKNOWN; FURTHER REVIEW IS WARRANTED.AN EA IS BEING OPENED TO GATHER FURTHER APPROPRIATE INFORMATION, CLARIFY ANY DEFECT TRENDS, AND TO ASSESS THE SAFETY IMPLICATIONS AND RISKS CONCERNING THESE FAILURES.