OBD-II Diagnostic Trouble Code
P0107 — Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
P0107 means the MAP or barometric pressure signal is below the minimum valid voltage. The ECM reads an impossibly low pressure, usually from a lost 5V reference, an open signal wire, a short to ground, or a failed sensor.
Severity 3/5
Truck-relevant
Service this week
Severity
Service this week
Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
Code
P0107
Category
Powertrain
Subsystem
Air Flow
Truck-relevant
Yes
What this means for truckers
P0107 (MAP Sensor Low Input) — manifold pressure sensor shorted to ground. ECM uses MAP for fuel mapping, so this hurts performance. Replacement: $50-150.
Before you replace parts — try this first
P0107 on the Air Flow system is most often open or shorted 5v reference, often pulled down by another shorted sensor on the same circuit — not a dead part. On commercial diesels especially, work these in order before spending money on parts:
- Confirm the symptoms. Match what your truck is doing to the Symptoms section below. If the code is set but the symptoms are not there, clear the code and re-test after a drive cycle — it may not return.
- Clean and dry the sensor connector. Water, road salt, or oil seeping into a connector is the #1 fake sensor failure. Disconnect, look for green corrosion or moisture, spray with electrical contact cleaner, dry, reseat. Many faults clear here for $0.
- Inspect the wiring harness. Trace the wire from the sensor toward the ECM — look for chafing against the engine block, melted insulation near the turbo or exhaust, or pinch points where a clamp has rubbed through.
- Test the sensor before swapping it. Most Common Causes (below) list the expected voltage or resistance range — a $20 multimeter saves a $300 sensor swap that does not fix the problem.
- Only then, replace the part. Use the OEM or a tier-1 aftermarket. Cheap sensors throw the same code in two weeks.
Symptoms
Check engine light, derate or low power on diesels because boost cannot be measured, and possible hard starting, rough running or stalling on gas engines. Other sensors sharing the 5V reference may also set codes.
Common causes
- CommonOpen or shorted 5V reference, often pulled down by another shorted sensor on the same circuit ($100–$500)
- CommonOpen signal wire or bad connector ($50–$300)
- CommonFailed MAP/boost sensor ($120–$400)
- RareECM internal fault ($900–$2500)
How to fix
Check for 5V reference at the sensor, and unplug other 5V sensors one at a time if it is low
When to use: When several 5V sensor codes are present at the same time
Check signal continuity from sensor to ECM and test for a short to ground
When to use: When the reference is good
Replace the MAP/boost sensor
When to use: When reference, ground and wiring are good but the output is still low
Affects most
No specific vehicle pattern found in our complaint database. This code can appear on any vehicle that supports OBD-II diagnostics.
Related
- → Browse all DTC trouble codes
- → Decode a VIN to check codes for your truck
- → Owner-operator maintenance guides
- → P0100 — Mass or Volume Air Flow Circuit
- → P0101 — Mass or Volume Air Flow Circuit Range/Performance
- → P0102 — Mass or Volume Air Flow Circuit Low Input
- → P0103 — Mass or Volume Air Flow Circuit High Input
- → P0104 — Mass or Volume Air Flow Circuit Intermittent
Frequently Asked Questions
Can I drive with code P0107?
P0107 is severity 3 — plan service within a few days. Performance is likely degraded already (you may feel reduced power, harsher shifts, or slightly worse fuel economy). Continuing to drive risks additional damage to adjacent components.
How much does it cost to fix P0107 on a commercial truck?
Total repair cost ranges $50–$2500 depending on the root cause. The cheapest fix is usually the first one listed below — Open or shorted 5V reference, often pulled down by another shorted sensor on the same circuit — which is also the most common. On commercial trucks the cost is usually higher than passenger vehicles due to part availability and shop labor rates ($120–185/hour at most truck shops, vs $90–130 at general auto shops). DIY-capable fixes (sensors, hoses, filters) are at the low end; major component replacements (turbo actuator, high-pressure fuel pump, transmission solenoid pack) are at the high end. Always diagnose with a scan tool BEFORE replacing parts — guessing wrong on a $1,500 turbo actuator when the actual issue was a $30 boost hose is a common expensive mistake.
Will P0107 fail a DOT inspection?
P0107 is generally not a direct DOT inspection fail item by itself. Inspectors focus on safety-critical systems (brakes, steering, tires, lights, hours-of-service). However, the check engine light alone can trigger additional inspection scrutiny. Best practice: fix the code and clear it before a planned inspection.
What's the difference between P0107 and related codes?
P0107 is closely related to: P0100 (Mass or Volume Air Flow Circuit), P0101 (Mass or Volume Air Flow Circuit Range/Performance), P0102 (Mass or Volume Air Flow Circuit Low Input), P0103 (Mass or Volume Air Flow Circuit High Input). These codes share the same subsystem (air-flow) and often appear together. If you see this code, scan for the full code list — fixing the root cause usually clears multiple companion codes at once. If only P0107 is set without the companions, the issue is more isolated.
How do I prevent P0107 from coming back after a repair?
For P0107 (Manifold Absolute Pressure/Barometric Pressure Circuit Low Input), prevention centers on the air flow system. Service air filter on time. Clean MAF sensor at every air filter change. Inspect intake boots/hoses for cracks — vibration kills them eventually.