Defroster/defogger/hvac system: heater coreRecall 79V-014 · Mack vehicles

MACK TRUCKS, INCORPORATED recall 79V-014 covers 358 Mack vehicles for a defroster/defogger/hvac system: heater core problem, reported to NHTSA on January 9, 1979.

Vehicles repairedNo manufacturer report yet

Vehicles affected3582 models

ReportedJan 9, 1979Owners notified Feb 2, 1979

Complaints since0Same system, after the recall

Source: NHTSA recall 79V014000 and manufacturer quarterly reports. Started by the manufacturer.

What's wrong

The problem

A DEFICIENCY IN THE ROUTING OF THE HEATER DUCT HOSE COULD ALLOW THE HOSE TO REST AGAINST A TERMINAL POST OF THE ACCESSORY RELAY. VIBRATION WILL EVENTUALLY CAUSE THE TERMINAL POST TO PENETRATE THE HOSE FABRIC AND SHORT CIRCUIT THE WIRE REINFORCEMENT AND OVERLOAD THE CIRCUIT.

What to do

The fix

DEALER WILL REPLACE THE PORTION OF THE EXISTING HOSE THAT IS CLOSEST TO THE ACCESSORY RELAY WITH AN ALL-RUBBER HOSE.

VEHICLE DESCRIPTION: TRUCKS.SYSTEM: ELECTRICAL; HEAT DUCT HOSE.CONSEQUENCES OF DEFECT: DUE TO A LACK OF CIRCUIT BREAKER PROTECTION, FIRE ANDLOSS OF ALL ELECTRICAL CIRCUITS, INCLUDING HEADLIGHTS, CAN OCCUR AND POSSIBLYLEAD TO A VEHICLE ACCIDENT.

Recall repairs are free. Confirm whether this recall is open on your vehicle by entering its VIN at nhtsa.gov/recalls.

2 models

Vehicles in this recall

Mack MC1978

Mack MR1978

Built from March 1, 1978 to November 17, 1978. Not every vehicle in these model years is included; check by VIN.