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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 DTC 🢒 DTC P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency

Object Number: 154524 Size: MF
Engine Controls Components
Fuel Pump and Fuel Level Sensors
OBD II Symbol Description Notice

Circuit Description

The mass air flow (MAF) sensor measures the amount of air which passes through the sensor into the engine during a given time. The powertrain control module (PCM) uses the mass air flow information to monitor engine operating conditions for fuel delivery calculations. A large quantity of air entering the engine indicates an acceleration or high load situation, while a small quantity of air indicates deceleration or idle. The MAF sensor produces a frequency signal which may be monitored using a scan tool. The frequency varies within a range of around 2000 Hertz at idle to about 10,000 Hertz at maximum engine load. DTC P0103 is set if the signal frequency from the MAF sensor is higher than the possible range of a normally operating MAF sensor.

Conditions for Running the DTC
    • The engine is running.
    • The TP angle is less than 50%.
    • The system voltage is more than 8 volts.

Conditions for Setting the DTC
    • The MAF signal frequency is more than 11,500 Hz.
    • The above conditions are present for longer than 0.5 seconds and 100 3X reference periods.

Action Taken When the DTC Sets
    • The PCM illuminates the malfunction indicator lamp (MIL) the first time the malfunction is detected.
    • The PCM calculates an airflow value based on idle air control valve position, the throttle position, the RPM and the barometric pressure.
    • The PCM stores conditions which were present when the DTC set as Freeze Frame and the Fail Records data.

Conditions for Clearing the MIL/DTC
    • The PCM turns the MIL off during the third consecutive trip in which the diagnostic has run and passed.
    • The history DTC clears after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC may be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

Diagnostic Aids

Inspect for the following conditions:

    • A faulty connection at the PCM. Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connections.
    •  Inspect the MAF sensor harness to ensure that the harness is not routed too closely to high voltage wires such as spark plug leads.
    • Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving the connectors and the wiring harnesses related to the MAF sensor. A change in the display indicates the location of the malfunction.

If DTC P0103 cannot be duplicated, the information included in the Fail Records data may be useful in determining vehicle mileage since the DTC was last set.

Test Description

The number(s) below refer to the step number(s) on the Diagnostic Table:

  1. This step verifies that the problem is present at idle.

    2.

  2. A frequency reading with the MAF sensor connector disconnected indicates an electromagnetic interference (EMI) related malfunction or a faulty connection.

    3.

  3. This vehicle is equipped with a PCM which utilizes an electrically erasable programmable read-only memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.

DTC P0103 - MAF Sensor Circuit High Frequency

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step  2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Start the engine.
  2. With the engine idling, use a scan tool in order to monitor MAF Frequency.

Is the MAF Frequency more than the specified value?

11,500 Hz

Go to Step 4

Go to Step 3

3
  1. Turn the ignition switch to the ON position.
  2. Review and record the scan tool Fail Records data.
  3. Operate the vehicle within the Fail Records conditions.
  4. Use the scan tool in order to monitor the Specific DTC info for DTC P0103.

Does the scan tool indicate DTC P0103 Failed This Ign?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the MAF sensor connector.
  3. Start the engine.
  4. Monitor the MAF Frequency on the scan tool.

Is the MAF Frequency at the specified value?

0 Hz

Go to Step 5

Go to Step 7

5
  1. Test for a faulty connection at the MAF sensor harness terminals.
  2. If a faulty connection is found, replace the loose terminal(s). Refer to Connector Repairs in Wiring Systems..

Was a problem found?

--

Go to Step  10

Go to Step  6

6

Replace the MAF sensor. Refer to Mass Airflow Sensor Replacement

Did you complete the repair?

--

Go to Step  10

--

7
  1. Inspect the MAF sensor harness for incorrect routing in the following locations:
    2. • Near the secondary ignition wires or thecoils.
    • Near other high voltage components (solenoids, relays, motors).
  2. If a problem is found, repair as necessary.

Was a problem found?

--

Go to Step  10

Go to Step  8

8
  1. Inspect the MAF signal circuit terminal connections at the PCM.
  2. If a faulty connection is found, replace the loose terminal(s). Refer to Connector Repairs in Wiring Systems.

Was a problem found?

--

Go to Step  10

Go to Step  9

9

Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .

Replace the PCM.

Did you complete the repair?

--

Go to Step  10

--

10
  1. Turn the ignition switch to the ON position.
  2. Review and record the scan tool Fail Records data.
  3. Clear any DTCs.
  4. Operate the vehicle within the Fail Records conditions.
  5. Use the scan tool in order to monitor the Specific DTC info for DTC P0103

Does the scan tool indicate that DTC P0103 Failed This Ign?

--

Go to Step 2

System OK