Code No. P0106: Manifold Absolute Pressure Sensor Range/Performance Problem

OPERATION

A power voltage of 5 V is applied to the manifold absolute pressure sensor power terminal (terminal No. 1) from the engine-ECU (terminal No. 72 and earthed to the engine-ECU (terminal No. 31) from the manifold absolute pressure sensor (terminal No. 3).
The sensor signal is inputted to the engine-ECU (terminal No. 37) from the manifold absolute pressure sensor output terminal (terminal No. 2).

FUNCTION

The manifold absolute pressure sensor converts the manifold absolute pressure into a voltage signal and inputs the signal to the engine-ECU.
In response to the signal, the engine-ECU corrects the fuel injection amount, etc.

TROUBLE JUDGMENT

Check Conditions

Battery positive voltage is 8 - 16 V
2 seconds later after the ignition switch has been in "ON" position or the engine has started up.
The following 3 conditions are formed:

The engine cooling water temperature is from -5 to 80 °C.
The intake air temperature is from -5 to 80 °C.
The atmospheric pressure is from 76 to 120 kPa.

Judgment Criterion

When an idle state and an engine rotation speed of 2,000 r/min continue for 3 seconds, manifold absolute pressures are read and the difference between them goes under 800 Pa for 1 second. <Vehicles without closed type DPF>
When an idle state and an engine rotation speed of 2,000 r/min continue for 3 seconds, manifold absolute pressure are read and the difference between them goes under 800 Pa for 5 seconds. <Vehicles with closed type DPF>

PROBABLE CAUSES

Vacuum hose clogged between manifold absolute pressure sensor and inlet manifold
Failed manifold absolute pressure sensor
Manifold absolute pressure sensor circuit harness damage or loose connector contact.
Failed engine-ECU

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III data list

Refer to Data List Reference Table .

Item 6: Manifold absolute pressure sensor

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions - How to Cope with Intermittent Malfunctions ).

	Go to Step 2 .

STEP 2. Check for vacuum hose for clogs between manifold absolute pressure sensor and inlet manifold.

Check whether the vacuum hose is clogged between the manifold absolute pressure sensor and the inlet manifold, which is caused by dirt and the hose folded. Also check the inside inlet manifold and the nipple that can be possibly contaminated with dirt.

Q. Is the check result normal?

	Go to Step 3 .

	Repair

STEP 3. Connector check: B-05 manifold absolute pressure sensor connector

Q. Is the check result normal?

	Go to Step 4 .

	Repair or replace the connector.

STEP 4. Perform voltage measurement at B-05 manifold absolute pressure sensor connector.

Use special tool test harness (MB991709) to connect connector, and measure at pick-up harness.
Ignition switch: ON
Voltage between terminal No. 1 and earth.

OK: 4.9 - 5.1 V

Q. Is the check result normal?

	Go to Step 6 .

	Go to Step 5 .

STEP 5. Connector check: D-213 engine-ECU connector

Q. Is the check result normal?

	Check and repair harness between B-05 (terminal No. 1) manifold absolute pressure sensor connector and D-213 (terminal No. 72) engine-ECU connector. Check power supply line for damage.

	Repair or replace the connector.

STEP 6. Perform voltage measurement at B-05 manifold absolute pressure sensor connector.

Use special tool harness (MB991709) to connect connector, and measure at pick-up harness.
Ignition switch: ON
Voltage between terminal No. 3 and earth.

OK: 0.5 V or less

Q. Is the check result normal?

	Go to Step 8 .

	Go to Step 7 .

STEP 7. Connector check: D-213 engine-ECU connector

Q. Is the check result normal?

	Check and repair harness between B-05 (terminal No. 3) manifold absolute pressure sensor connector and D-213 (terminal No. 31) engine-ECU connector. Check earthing line for damage.

	Repair or replace the connector.

STEP 8. Perform voltage measurement at B-05 manifold absolute pressure sensor connector.

Use special tool harness (MB991709) to connect connector, and measure at pick-up harness.
Ignition switch: ON
Voltage between terminal No. 2 and earth.

OK: The voltage should be 0.7 - 1.2 V. When the accelerator pedal is quickly depressed from the idling state, the voltage temporarily rises.

Q. Is the check result normal?

	Go to Step 9 .

	Replace the manifold absolute pressure sensor.

STEP 9. Perform voltage measurement at D-213 engine-ECU connector.

Measure engine-ECU terminal voltage.
Ignition switch: ON
Voltage between terminal No. 37 and earth.

OK: The voltage should be 0.7 - 1.2 V. When the accelerator pedal is quickly depressed from the idling state, the voltage temporarily rises.

Q. Is the check result normal?

	Go to Step 10 .

	Check and repair harness between B-05 (terminal No. 2) manifold absolute pressure sensor connector and D-213 (terminal No. 37) engine-ECU connector. Check output line for damage.

STEP 10. Connector check: D-213 engine-ECU connector.

Q. Is the check result normal?

	Go to Step 11 .

	Repair or replace the connector.

STEP 11. M.U.T.-III data list

Refer to Data List Reference Table .

Item 6: Manifold absolute pressure sensor

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing

). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns

). After registering the injector identification code, the vehicle equipped with the closed type DPF carries out the forcible DPF regeneration. (Refer to GROUP 17 - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration