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P0107 Code Explained: Manifold Absolute Pressure (MAP) / Barometric Pressure Circuit Low Input Causes, Symptoms & Fixes

P0107 Code Explained highlight image showing a Manifold Absolute Pressure sensor circuit low-input fault, low-voltage warning, damaged signal wiring, Check Engine light, Pro Street TV logo, and www.ProStreetOnline.com branding.

If your OBD-II scanner displays P0107, your vehicle’s Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected that the Manifold Absolute Pressure (MAP) or Barometric Pressure (BARO) sensor signal voltage has dropped below the minimum acceptable threshold.

The generic OBD-II definition for P0107 is:

Manifold Absolute Pressure/Barometric Pressure Circuit Low Input

Unlike P0105, which indicates a general circuit malfunction, or P0106, which points to an implausible or inaccurate sensor reading, P0107 specifically means the MAP sensor voltage is too low.

In many vehicles, the PCM expects the MAP sensor to produce a signal between approximately 0.5 and 4.5 volts, depending on engine load. If the signal remains below the calibrated minimum voltage for a specified period, the PCM stores P0107 and illuminates the Check Engine Light.

While a failed MAP sensor is a common cause, low signal voltage can also result from damaged wiring, short circuits, poor electrical connections, a missing 5-volt reference, faulty grounds, excessive engine vacuum, or internal PCM issues.

Fortunately, most P0107 repairs can be diagnosed with a quality scan tool, digital multimeter, and careful inspection of the intake and electrical systems.

Alternate Manufacturer Definitions

Depending on the manufacturer or scan tool, P0107 may also appear as:

Although the wording varies, each definition indicates that the PCM has detected an abnormally low voltage signal from the MAP or BARO sensor.

P0107 Quick Facts

ItemInformation
Diagnostic CodeP0107
Generic DefinitionMAP/BARO Circuit Low Input
CategoryPowertrain
SystemAir Intake / Engine Management
Fault TypeLow Signal Voltage
SeverityModerate to High
Safe to Drive?Sometimes
Common CausesFaulty MAP sensor, short to ground, damaged wiring, vacuum problems
Common SymptomsRough idle, hesitation, hard starting, reduced power
Typical Repair Cost$40–$1,200+

What Does the P0107 Code Mean?

The MAP sensor constantly measures pressure inside the intake manifold and sends that information to the PCM.

As engine load changes:

When the MAP signal voltage remains lower than expected, the PCM assumes the sensor can no longer accurately report manifold pressure.

To protect the engine, the PCM substitutes calculated values and stores P0107.

What Does “Low Input” Mean?

A Low Input code does not necessarily mean manifold pressure itself is low.

Instead, it means the electrical voltage returning from the MAP sensor is lower than the PCM expects.

Possible reasons include:

What Is the MAP Sensor?

The Manifold Absolute Pressure (MAP) sensor measures pressure inside the intake manifold.

The PCM uses this information to calculate:

Without an accurate MAP signal, engine performance can quickly deteriorate.

How the MAP Sensor Works

Most MAP sensors contain:

As manifold pressure changes:

Typical voltage values include:

Operating ConditionTypical Voltage
Key On, Engine Off4.0–4.8 V
Warm Idle0.9–1.8 V
Light Cruise1.5–2.8 V
Heavy Load3.5–4.5 V

Values vary by manufacturer.

How the PCM Detects P0107

The PCM continuously compares MAP voltage with:

P0107 may set if:

Some manufacturers require multiple failures before illuminating the MIL.

P0107 vs P0105, P0106, P0108 and P0109

CodeDescriptionGeneral Fault
P0105MAP/BARO Circuit MalfunctionGeneral circuit fault
P0106MAP/BARO Range/PerformanceImplausible sensor readings
P0107MAP/BARO Circuit Low InputVoltage too low
P0108MAP/BARO Circuit High InputVoltage too high
P0109MAP/BARO Circuit IntermittentSignal drops in and out

A simple way to remember them:

Common Symptoms of P0107

Symptoms vary depending on how inaccurate the pressure signal becomes.

Common symptoms include:

Some vehicles may exhibit only a Check Engine Light.

Can P0107 Cause Hard Starting?

Yes.

Incorrect manifold pressure information affects startup fuel calculations.

The PCM may command:

The result can be:

Can P0107 Cause Reduced Power?

Absolutely.

Without reliable MAP information, the PCM often limits:

Many vehicles enter reduced-power or limp mode.

Can P0107 Affect Turbocharged Engines?

Yes.

Turbocharged vehicles rely heavily on accurate MAP readings.

If the MAP voltage remains too low, the PCM may:

Is P0107 Serious?

P0107 is considered a moderately serious to serious diagnostic trouble code.

Ignoring it may result in:

Prompt diagnosis is recommended.

Can You Drive with P0107?

Sometimes.

Short trips may be possible if:

Avoid driving if:

Can a Short to Ground Cause P0107?

Yes.

A shorted signal wire is one of the most common causes.

If the signal wire contacts:

The PCM may receive nearly zero volts and immediately set P0107.

Can a Bad Ground Cause P0107?

Yes.

Poor sensor grounding can distort voltage readings.

Always inspect:

before replacing the sensor.

Can a Missing 5-Volt Reference Cause P0107?

Absolutely.

Many engine sensors share the same 5-volt reference circuit.

If another sensor shorts the reference voltage:

Always verify reference voltage before replacing components.

25 Common Causes of P0107

The most common causes include:

  1. Failed MAP sensor
  2. Signal wire shorted to ground
  3. Missing 5-volt reference
  4. Poor sensor ground
  5. Corroded connector terminals
  6. Loose connector
  7. Broken signal wire
  8. Damaged wiring harness
  9. Water intrusion
  10. Oil contamination
  11. Rodent damage
  12. Vacuum hose collapse
  13. Restricted MAP sensor port
  14. Intake manifold contamination
  15. Faulty BARO sensor
  16. Shared 5-volt circuit fault
  17. Charging system voltage problems
  18. Poor battery connections
  19. Low battery voltage
  20. PCM connector corrosion
  21. Incorrect aftermarket MAP sensor
  22. Engine timing problems
  23. Internal PCM software issue
  24. Internal PCM failure
  25. Previous improper repairs

The majority of repairs involve the MAP sensor, wiring, connectors, or reference voltage—not PCM replacement.

Failed MAP Sensor

Internal electronic failure is the single most common cause of P0107.

Heat, vibration, contamination, and age can cause the sensor to output a permanently low voltage.

Always verify:

before replacing the sensor.

Wiring Problems

Electrical faults frequently trigger P0107.

Inspect for:

High resistance or a short to ground can lower signal voltage enough to trigger the code.

PCM Failure

Although possible, PCM failure is uncommon.

Always eliminate:

before condemning the PCM.

Proper diagnosis prevents unnecessary and expensive module replacement.

Because P0107 is a low-input circuit code, the most important question is not whether the engine has low manifold pressure. The real issue is whether the PCM is receiving electrical voltage below the expected threshold from the MAP or BARO circuit.

A proper diagnosis must determine whether the low reading is caused by:

The following process is designed to separate the likely causes before parts are replaced.

How to Diagnose the P0107 Code

Step 1: Confirm the Code

Connect a capable OBD-II scan tool and record:

Do not clear the code until all freeze-frame information has been saved.

Step 2: Check for Related Trouble Codes

Look for additional codes involving:

Related codes may include:

Multiple low-input codes often suggest a shared reference-voltage problem rather than several failed sensors having a group meeting.

Step 3: Review Freeze-Frame Data

Check the conditions under which P0107 was stored.

Review:

If the code set immediately after startup, focus on:

If it set during driving, inspect the harness for movement-related shorts or intermittent grounding.

Step 4: Perform a Visual Inspection

Inspect the MAP sensor, wiring, and connector.

Look for:

Pay close attention to wiring near:

Step 5: Inspect the MAP Sensor Connector

Disconnect the MAP sensor connector and inspect each terminal.

Check for:

A poor terminal fit can pull the signal voltage low without causing a complete circuit open.

Step 6: Check Key-On MAP Data

Turn the ignition on without starting the engine.

The MAP reading should be reasonably close to current barometric pressure.

At sea level, this is typically near:

If the scan tool displays an extremely low value, near-zero voltage, or unrealistic pressure, continue with electrical testing.

Step 7: Disconnect the MAP Sensor

With the key off, unplug the MAP sensor.

Turn the key on again and monitor scan data.

Depending on the system, the PCM may:

If the low signal changes significantly when the sensor is unplugged, the sensor may be internally shorted.

If the value remains low, wiring or PCM issues become more likely.

Step 8: Verify the Five-Volt Reference

Use a digital multimeter to test the reference-voltage circuit.

Most MAP sensors should receive approximately:

If reference voltage is missing or low, inspect:

Do not replace the MAP sensor until the reference circuit is verified.

Step 9: Check for a Shared Reference-Circuit Fault

Many sensors share a common five-volt supply.

Possible shared components include:

Disconnect shared sensors one at a time while monitoring reference voltage.

If voltage returns when one sensor is unplugged, that sensor or its wiring may be shorting the circuit.

Step 10: Test the Sensor Ground

Measure voltage drop between the MAP sensor ground and battery negative.

The reading should be very low.

A poor ground may be caused by:

A continuity test alone may miss resistance that appears only under load.

Step 11: Test the Signal Circuit

Back-probe the MAP signal wire.

Typical signal voltage may be approximately:

If the signal remains near zero, determine whether it is being pulled low by:

Step 12: Check for a Signal Wire Short to Ground

Turn the ignition off and disconnect both:

Measure resistance between the signal wire and ground.

Very low resistance may indicate a short.

Inspect the harness for:

Follow the manufacturer wiring diagram before disconnecting or probing PCM circuits.

Step 13: Check Signal-Wire Continuity

Measure continuity between the MAP connector and the PCM terminal.

Look for:

A wire can pass a basic continuity test and still fail under vibration or heat, so load testing may be required.

Step 14: Perform a Wiggle Test

Monitor MAP voltage while gently moving:

Watch for:

If the voltage changes during movement, the fault is likely in the harness or connector.

Step 15: Inspect the MAP Sensor Port

Remove the MAP sensor if accessible.

Inspect the port for:

Although a blocked port more commonly causes a range/performance code, severe contamination can contribute to an abnormally low output.

Use only manufacturer-approved cleaner.

Step 16: Inspect Vacuum Hoses

If the MAP sensor is remotely mounted, inspect the vacuum hose for:

A restricted hose can prevent pressure changes from reaching the sensor correctly.

Step 17: Verify Battery and Charging Voltage

Check:

Low system voltage can affect sensor circuits and PCM operation.

Typical values include:

Use manufacturer specifications whenever available.

Step 18: Check Engine and Chassis Grounds

Inspect:

Poor grounds can create multiple unrelated sensor codes and unusual voltage readings.

Step 19: Test the MAP Sensor with a Vacuum Pump

If the sensor can be bench-tested, connect:

Apply vacuum gradually.

The signal voltage should change smoothly without:

Replace the sensor if it fails to respond correctly despite proper reference voltage and ground.

Step 20: Compare Scan Data with Direct Voltage

Compare:

If the measured sensor signal is correct but the scan data is wrong, suspect:

Step 21: Check for Aftermarket Modifications

Inspect for:

An incorrectly scaled or improperly wired aftermarket MAP sensor can trigger P0107.

Step 22: Inspect PCM Connectors

Disconnect the battery if required by the manufacturer.

Inspect PCM connectors for:

Never force test probes into terminals because that can create the exact connector problem you are supposedly diagnosing.

Step 23: Check Technical Service Bulletins

Search manufacturer service information for:

A known bulletin can reduce diagnostic time and prevent unnecessary parts replacement.

Step 24: Test PCM Inputs and Outputs

If the sensor, wiring, grounds, reference voltage, and connectors test correctly, verify PCM operation.

Confirm:

PCM replacement should only be considered after all external causes are eliminated.

Step 25: Clear the Code and Verify the Repair

After completing repairs:

  1. Clear all diagnostic codes.
  2. Start the engine.
  3. Monitor MAP voltage at idle.
  4. Verify MAP changes with throttle input.
  5. Confirm key-on MAP and BARO correlation.
  6. Complete a drive cycle.
  7. Rescan for pending codes.
  8. Confirm readiness monitors complete.

The repair is successful only when P0107 does not return and sensor data remains stable.

Common Repairs for P0107

Common repairs include:

P0107 Repair Costs

RepairEstimated Cost
Diagnostic inspection$100–$220
Connector cleaning$20–$100
MAP sensor cleaning$20–$100
Vacuum hose replacement$20–$150
MAP connector replacement$75–$250
Wiring repair$100–$500
Ground repair$100–$350
MAP sensor replacement$120–$450
Shared sensor replacement$150–$600
PCM software update$100–$300
PCM replacement and programming$1,000–$3,500+

Actual cost depends on the vehicle, labor rate, accessibility, and whether the fault affects a shared reference-voltage circuit.

A $150 sensor may fix the problem. A damaged wire hidden under the intake manifold may cost more to locate than the part itself, because electricity enjoys making simple problems expensive.

Common P0107 Diagnostic Mistakes

Replacing the MAP Sensor Without Testing Voltage

A new sensor will not fix:

Always test the circuit first.

Confusing Low Voltage with Low Manifold Pressure

P0107 refers to low electrical input, not simply low intake pressure.

The distinction matters because the repair path is electrical before it is mechanical.

Ignoring Related Sensor Codes

Multiple low-input codes often point to a shared five-volt circuit fault.

Replacing several sensors individually can become a very expensive way to discover one shorted wire.

Using Only a Continuity Test

A wire can show continuity while still having excessive resistance.

Use:

when necessary.

Overlooking Ground Problems

Poor grounds can affect several circuits at once and create inconsistent scan data.

Inspect the full ground path, not only the sensor connector.

Failing to Inspect Connector Terminal Tension

A connector may look perfect while the terminals fail to grip the sensor pins.

Loose terminals can cause low or intermittent voltage.

Blaming the PCM Too Soon

PCM failure is possible but rare.

Verify:

before replacing the module.

Installing a Cheap Aftermarket Sensor

Some low-cost sensors produce incorrect voltage ranges even when brand new.

Use an OEM or reputable replacement with the correct calibration.

Manufacturer-Specific P0107 Notes

Chevrolet, GMC, Cadillac and Buick

Inspect:

GM vehicles may set several sensor codes when one component pulls down the reference circuit.

Ford and Lincoln

On EcoBoost and naturally aspirated engines, inspect:

Ford systems may use more than one pressure sensor, so confirm the exact circuit identified by the code.

Toyota, Lexus and Scion

Check:

Toyota systems are often intolerant of poorly calibrated aftermarket sensors.

Honda and Acura

Inspect:

Honda vehicles commonly rely on the MAP sensor for load calculations, so drivability symptoms may be noticeable.

Nissan and Infiniti

Check:

Compare MAP data with MAF and throttle-position data.

Hyundai, Kia and Genesis

Inspect:

A shared five-volt fault may set several unrelated codes.

Volkswagen and Audi

On turbocharged engines, inspect:

Use manufacturer-capable scan data to compare sensor voltage and calculated boost pressure.

BMW and MINI

Common areas include:

Avoid replacing the sensor until the reference and signal circuits are measured directly.

Mercedes-Benz

Inspect:

Manufacturer-level scan tools may provide more accurate pressure-sensor data than a generic reader.

Subaru

On turbocharged models, inspect:

Incorrect sensor scaling after modification can trigger low-input codes.

Chrysler, Dodge, Jeep and Ram

Inspect:

Many Chrysler systems rely heavily on MAP data, so a low signal may cause immediate limp mode.

Preventative Maintenance

To reduce the chance of future P0107 faults:

Electrical failures often begin as minor connector or insulation damage. Fixing those problems early is cheaper than waiting for the harness to become modern art.

Frequently Asked Questions About P0107

What does the P0107 code mean?

P0107 means the PCM has detected that the MAP or BARO sensor signal voltage is below the minimum expected level.

Does P0107 mean the MAP sensor is bad?

Not always.

Common causes also include:

Is P0107 a low-pressure code?

No.

It is a low electrical input code. The PCM is seeing voltage that is too low.

Can a short to ground cause P0107?

Yes. A shorted signal wire can pull MAP voltage close to zero and trigger the code immediately.

Can a bad ground cause P0107?

Yes. Ground resistance can distort the signal or prevent the sensor from operating correctly.

Can low battery voltage cause P0107?

It can contribute, especially during cranking or when the charging system is unstable.

Can a shared five-volt circuit cause P0107?

Yes. Another sensor may short the shared reference supply and pull the MAP circuit low.

Can I drive with P0107?

A short trip may be possible if the engine runs normally, but avoid driving if the vehicle stalls, enters limp mode, misfires, or lacks enough power for safe acceleration.

What should MAP voltage be with the engine off?

Many analog sensors produce approximately 4.0–4.8 volts with the key on and engine off.

Always verify the exact specification for the vehicle.

What should MAP voltage be at idle?

Typical voltage is often around 0.9–1.8 volts at warm idle, although engine design and altitude affect the reading.

How do you test a MAP sensor?

Verify:

The voltage should change smoothly as manifold pressure changes.

How much does it cost to repair P0107?

Simple connector or wiring repairs may cost under $200. MAP sensor replacement often costs $120–$450. PCM-related repairs can exceed $1,000.

Will clearing the code fix P0107?

No. Clearing the code only resets the warning. The code will return if the low-voltage condition remains.

What is the difference between P0106 and P0107?

P0106 indicates an implausible or inaccurate MAP/BARO reading.

P0107 specifically indicates signal voltage that is too low.

What is the difference between P0107 and P0108?

P0107 means the signal is too low.

P0108 means the signal is too high.

Can an aftermarket MAP sensor cause P0107?

Yes. A sensor with the wrong calibration or connector pinout can produce a low signal even if it physically fits.

Final Thoughts

The P0107 MAP/Barometric Pressure Circuit Low Input code means the PCM is receiving less signal voltage than expected from the manifold-pressure circuit.

The MAP sensor may have failed, but low-input faults are also commonly caused by:

The fastest diagnostic path is to verify the five-volt reference, ground, and signal voltage before replacing anything.

If the circuit checks correctly, test the sensor under changing vacuum and compare direct voltage with scan-tool data. Only after the wiring and sensor are proven good should PCM failure enter the conversation.

P0107 is usually fixable without major engine work. It simply requires electrical testing instead of the traditional diagnostic method of replacing whatever part is easiest to reach.

Related Pro Street Diagnostic Guides

Related MAP and BARO Codes

Related Mass Air Flow Codes

Complete OBD-II Code Libraries

Link this article to P0106, P0108, and P0109 to strengthen the full MAP/BARO diagnostic cluster across the Pro Street OBD-II library.

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