NHTSA Recall 78V132000
Filed by Volvo Trucks North America. Component: Service Brakes, Air. Reported 1978-06-12. An estimated 39 vehicles are affected. Recall repairs are free at any authorized dealer.
Defect
THE INVOLVED VEHICLES MAY HAVE BEEN BUILT WITH POWER UNIT ANTI-SKID LOGIC MODULES ON TAG AXLE INSTALLATIONS INSTEAD OF THE CORRECT TRAILER TYPE MODULES. SINCE THE TAG AXLE SENSOR OUTPUT IS LESS THAN THAT OF THE POWER UNIT SENSOR, IT REQUIRES THE MORE SENSITIVE TRAILER MODULE. AS SENSOR OUTPUT OVER TIME DROPS BELOW MINIMUM REQUIREMENTS, ONE OF TWO THINGS WILL HAPPEN: (1) THE ANTI-LOCK SYSTEM ON THE TAG AXLE WILL SHUT DOWN AND THE CAB MOUNTED FAULT LAMP WILL LIGHT OR (2) THE SYSTEM WILL BECOME INOPERATIVE WITHOUT ACTIVATING THE FAULT LIGHT. THIS FAILS TO CONFORM TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKES".
What the manufacturer will do
DEALER WILL REPLACE THE INCORRECT ANTI-LOCK MODULE WITHOUT CHARGE TO OWNER.
Notes
VEHICLE DESCRIPTION: TRUCK TRACTORS.SYSTEM: SERVICE BRAKES; VACUUM BRAKE SYSTEM.CONSEQUENCES OF DEFECT: IF THE SYSTEM BECOMES INOPERATIVE, A BRAKE LOCK-UP,LOSS OF VEHICLE CONTROL AND AN ACCIDENT COULD OCCUR WITHOUT PRIOR WARNING.NOTE: THE ELECTRICAL POWER TO THE ANTI-LOCK SYSTEM SHOULD BE DISCONNECTED BYREMOVING THE ANTI-LOCK SYSTEM FUSE UNTIL THE DEFECT CAN BE CORRECTED.