PACCAR Fault Code P0072: Ambient Temperature – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (C78)

Code details

Manufacturer

PACCAR (Kenworth & Peterbilt)

Applies to

PACCAR MX-13 (2017–2020)

Fault code

P0072

J1939 SPN

171

FMI

4 — Voltage below normal, or shorted to low source

Truck models in source

Kenworth T680, T880, W900, T800; Peterbilt 579, 389, 567, 367

What to do next

• Read active and inactive codes with the OEM service tool and note the occurrence count.
• FMI 4 tells the shop the type of failure to test for: voltage below normal, or shorted to low source.
• Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.

Related fault codes

• PACCAR Fault Code P0073 — Ambient Temperature – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (C78)
• PACCAR Fault Code P009A — Ambient Temperature – Data Erratic, Intermittent, or Incorrect
• PACCAR Fault Code U1070 — CAN Communication – Message (AMB) Out of Range, Ambient Temperature From Vehicle Control System
• International SA 23 SPN 171 FMI 3 — Fault on Analog Input 3 above normal when used for outside temperature
• International SA 23 SPN 171 FMI 4 — Fault on Analog Input 3 below normal when used for outside temperature
• International Fault Code SPN 171 FMI 0 — Ambient Air Temperature: Data Valid But Above Normal Operational Range – Most Severe Level
• International Fault Code SPN 171 FMI 2 — Ambient Air Temperature: Data Erratic, Intermittent Or Incorrect
• International Fault Code SPN 171 FMI 3 — Ambient Air Temperature : Voltage Above Normal, Or Shorted To High Source