P0102 — Mass Airflow Circuit Low Input
What it means: Mass Airflow Circuit Low Input.
How serious / can you keep driving: Serious. Power derate likely — plan to stop soon.
Check first: Check MAF signal wire for ground fault
Don't risk it — look up listed providers near you and give them this code when you call.
Listed providers nearest Phoenix, AZ
Closest first. Tell them P0102 and what the truck is doing. RoadService.app lists these providers and does not employ them or carry out the repair.
- 0.0 mi away — based in Phoenix, AZ · (623) 304-4187
- 0.0 mi away — based in Phoenix, AZ · (480) 458-7715
- 0.0 mi away — based in Phoenix, AZ · (480) 530-7347
Seen on: Heavy Truck
What P0102 means
Mass Airflow Circuit Low Input. Common causes: MAF sensor signal too low.
How serious is it?
Serious. Power derate likely — plan to stop soon.
Most likely causes
- MAF sensor signal too low
- Short to ground
- failed sensor
First moves (roadside)
- Check MAF signal wire for ground fault
- replace sensor
FAQ
Mass Airflow Circuit Low Input. Common causes: MAF sensor signal too low.
Serious — Power derate likely — plan to stop soon.
The most common cause is: MAF sensor signal too low. Other possibilities include Short to ground; failed sensor.
Power derate likely — plan to stop soon. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Related codes
Codes that commonly appear alongside P0102, or share the same subsystem.
- Engine Protection — Power Derate Active (SPN 1569 FMI 31)
- Intake Manifold (Charge Air) Temp — High (SPN 105 FMI 0)
- Turbo Boost Pressure — High / Overboost (SPN 1127 FMI 16)
- Boost pressure high (SPN 102 FMI 0)
- Boost sensor — voltage low (SPN 102 FMI 4)
- Intake manifold temp — voltage high (SPN 105 FMI 3)
- Intake manifold temp — voltage low (SPN 105 FMI 4)
- Injection control pressure low (HEUI — older engines) (SPN 164 FMI 1)
Same symptom: Low boost / low power
Other air-path codes that arrive as a truck that will not pull the hill it pulled yesterday.
- Turbo boost pressure high (SPN 1127 FMI 0) · Engine
- Turbo compressor inlet temp high voltage (SPN 1172 FMI 3) · Engine
- Turbo compressor inlet pressure — high voltage (SPN 1176 FMI 3) · Engine
- VGT actuator position — not responding (SPN 2795 FMI 7) · Engine
- VGT position — not responding (similar to 2795) (SPN 5571 FMI 7) · Engine
- Turbo turbine inlet temp — high voltage (SPN 5856 FMI 3) · Engine
Find a mechanic or related guides
General diagnostic guidance for diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack and more). Not a substitute for a scan-tool diagnosis on your specific truck.