P0102 OBD-II Trouble Code: Mass Airflow (MAF) Circuit Low Voltage Input

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0102 code

P0102 is a diagnostic trouble code (DTC) for "Mass Airflow (MAF) Circuit Low Voltage Input". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $114.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford $114.99 $20.0
Toyota $114.99 $20.0
BMW $124.99 $20.0
SCHEDULE P0102 DIAGNOSTIC Get a fair and transparent estimate upfront

P0102 Trouble code definition

Mass Airflow (MAF) Circuit Low Voltage Input

  • The code P0102 code is often associated with P0100, P0101, P0103 or P0104 trouble codes as they are closely related.

What the P0102 code means

P0102 is the general code for a problem with the Mass Airflow (MAF) Sensor having a low voltage output to the Engine Control Unit (ECU).

What causes the P0102 code?

The MAF Sensor has low voltage output problems which may have several causes.

  • The source of the problem is the sensor range voltage is lower than normal or required by the ECU to function properly.

  • The most obvious problem is restricted airflow from the air cleaner to the MAF sensor which can be a clogged air filter.

  • The wiring or MAF sensor may be too close to higher voltage consumption components, especially alternators, ignition wires, etc. which can give false readings.

  • The MAF sensor can also be dirty or partially plugged with carbon causing a low reading. Many MAF units have screens and they can get clogged up easily, clean using a CRC 05110 spray cleaner.

  • MAF sensors must operate within specific ranges to send correct signals for the ECU to adjust correctly for proper engine operation and inputs from other sensors..

What are the symptoms of the P0102 code?

  • P0102 code will be normally preceded by the Check Engine Light coming on the dashboard display.

  • The engine can run near normal but it may run slightly erratically, have less power and idle inconsistently.

  • The vehicle may have too low of fuel consumption, which could cause internal engine problems.

How does a mechanic diagnose the P0102 code?

  • P0102 is diagnosed with an OBD- II scan tool. A qualified technician should then reset the OBD- II fault codes and road test the vehicle to see if the code returns. He can observe this by watching it live on his scanner while driving.

  • If the code does comes back, the mechanic will need to do a thorough visual inspection to determine any electrical connector, wiring, sensor, air cleaner, is plugged or damaged MAF unit.

  • If no problems are noted, then the next step is to have the mechanic do a circuit test with a multimeter that has a digital display to show sampling rate and sensor range readings to determine if the MAF sensor output is really too low or there is another cause.

Common mistakes when diagnosing the P0102 code

  • Diagnostic errors are largely due to not following the correct procedure. First, follow the test procedure for the wiring and sensor.

  • Do not buy a MAF sensor unless the other tests indicate no problem. Before buying a MAF sensor, try cleaning it with a specialized spray cleaner, like CRC 05110 made for MAF sensors, as these often get considerable carbon build up from the emission system, especially at idle.

  • The air filter may be very dirty causing the sensor to show low air flow voltage due to air flow restriction.

How serious is the P0102 code?

  • The P0102 code will generally not prevent the car from driving. The MAF sensor issue can cause both limited and excessive fuel consumption, rough operation and difficulty starting in certain circumstances, so it is best to have a mechanic inspect it at your first opportunity.

  • Occasionally, if no problems are found, reset the fault codes and then retest to see if the warning light and code return.

  • Often times, if the engine warning light came on immediately at start up, the OBD- II system can be reset and the vehicle will operate normally.

What repairs can fix the P0102 code?

The most common repairs to address the P0102 code are as follows:

  • Verify the code with a scanner. Reset the fault codes and perform a road test with normal driving.

  • If the P0102 code comes back, then it is important to follow the test procedure.

  • Inspect the electrical connector to the MAF to insure it is attached correctly. Disconnect it and then reinstall to insure fresh electrical connection to remove any corrosion on the contacts.

  • Thoroughly inspect for wiring being frayed, damaged, or broken on the connector. Repair or replace as necessary.

  • Check for vacuum leaks on the intake manifold hose and fittings, especially on older cars.

Additional comments for consideration regarding the P0102 code

Many vehicles with mileage over 100,000 have momentary sensor problems that usually occur during start up or prolonged stress situations on the drive train.

If the engine warning light comes on and the vehicle seems to be operating normally, the OBD-II system can be reset using the scanner and the problem may not reoccur. This is why it is important to verify the fault and reset it before doing any repairs.

Need help with a P0102 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
P0102
trouble codes

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0102 code.

SCHEDULE P0102 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(7400)

Rating Summary
6879
249
58
41
173
6879
249
58
41
173
 at YourMechanic

David

13 years of experience
393 reviews
David
13 years of experience
Chevrolet Malibu L4-2.4L - Check Engine Light is on Inspection - Marietta, Georgia
He explained everything to me in detail on what I needed to know about my car. Definitely recommend him for getting the job done.
 at YourMechanic

Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Toyota Camry L4-2.2L - Check Engine Light is on - Las Vegas, Nevada
Raymond did a great job however I was charged for two hours labor and he was only here less than 45 minutes. should I expect this on future appointments with your mechanic ?
 at YourMechanic

Shane

17 years of experience
217 reviews
Shane
17 years of experience
Volkswagen EuroVan V6-2.8L - Check Engine Light is on Inspection - Austin, Texas
Arrived on time. Explained the issues he found and how he will fix it. I have parts on order and will schedule an appointment to have Shane install the parts when they arrive.
 at YourMechanic

Kanstantsin

19 years of experience
51 reviews
Kanstantsin
19 years of experience
Ford F-150 V8-4.6L - Check Engine Light is on Inspection - Littleton, Colorado
Kanstantsin arrived early. Was very courteous and professional. Will highly recommend to anyone. Thank you Kanstantsin.


Related questions

1999 firebird every now and then dies while driving and low engine power light comes on
A bad mass airflow (MAF) sensor (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-mass-airflow-sensor) can cause loss of power, no starts, and lean or rich conditions. If cleaning the sensor did not get rid of the P0102 trouble code (https://www.yourmechanic.com/article/p0102-obd-ii-trouble-code-mass-airflow-maf-circuit-low-voltage-input-by-john-nelson), then replace the MAF sensor (https://www.yourmechanic.com/services/mass-airflow-sensor-replacement) and...
Rough idle after replacing Mass Air Flow Sensor - trouble codes P0171 and P0102
The P0171 (https://www.yourmechanic.com/article/p0171-obd-ii-trouble-code-system-too-lean-bank-1-by-andrew-quinn) refers to a possible lack of fuel pressure, a leak in the intake air system, or a possible vacuum leak. The P0102 (https://www.yourmechanic.com/article/p0102-obd-ii-trouble-code-mass-airflow-maf-circuit-low-voltage-input-by-john-nelson) also leans towards a leak in the intake air system. It is possible that...
Instrument panel lights are on - codes P0102, P0069
Both of these sensors have to do with sending air mass and pressure information to the engine computer. It is likely you have a vacuum leak or these sensors are starting to fail and are offering the engine computer false...

More related articles

P0366 OBD-II Trouble Code: Camshaft Position Sensor "B" Circuit Range/Performance (Bank 1)
P0366 P0366 code definition The P0366 code is defined as an incorrect voltage reading from the camshaft position sensor circuit, specifically for the engine bank 1 camshaft sensor B. What the P0366 code means In order to control fuel injection...
P0470 OBD-II Trouble Code: Exhaust Pressure Sensor Malfunction
P0470 means the sensor in charge of assessing exhaust pressure isn't working due to the back pressure sensor or poor electrical connection.
P0414 OBD-II Trouble Code: Secondary Air Injection System Switching Valve A Circuit Shorted
P0414 code means that there is an issue with the secondary air system due to a failed air pump, a short in the wiring harness, or a faulty hose.

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com