Vehicle recall 79V014000 · January 9, 1979
Mack MC and MR
A deficiency in the routing of the heater duct hose could allow the hose to rest against a terminal post of the accessory relay.
Source: NHTSA data as of September 22, 2026. Last refreshed Sep 23, 2026, 2:43 AM UTC.
- Summary
- 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.
- Remedy
- Dealer will replace the portion of the existing hose that is closest to the accessory relay with an all-rubber hose.
- Notes
- 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 details
- NHTSA campaign
- 79V014000
- Reported to NHTSA
- January 9, 1979
- Filed by
- MACK TRUCKS, INCORPORATED
- Owner notification
- February 2, 1979
- Vehicles potentially affected
- 358
- Initiated by
- the manufacturer
- Components
- Visibility › Defroster/defogger/HVAC system › Heater core
Vehicles covered
As listed by NHTSA. A recall usually covers only some vehicles of each model and year, often a production date range.
Has your Mack been repaired?
Recalls here come from NHTSA’s records for the model and year. Not every vehicle of a model is included in every recall, and this site can’t see whether a repair has been done. Only a VIN lookup can tell you that.
NHTSA’s VIN search doesn’t show recalls that were already repaired, recalls more than 15 years old, or some small manufacturers’ recalls. A Mack dealer can also check your VIN. Recall repairs are free.