Code No. P1963: Trustful Check Air Flow Sensor

FUNCTION

Compare the actual measurement of volumetric efficiency by an air flow sensor signal with volumetric efficiency estimated from a throttle position sensor (main and sub) signal.

TROUBLE JUDGMENT

Check Condition

Plausibility error of the throttle position sensor (main) is detected.
Plausibility error of the throttle position sensor (sub) is detected.

Judgement Criterion

Difference between the volumetric efficiency estimated by the throttle position sensor (main) and the volumetric efficiency estimated by the throttle position sensor (sub) is less than 8.8 %.

PROBABLE CAUSES

Failed air flow sensor
Harness damage in air flow sensor circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is any other diagnosis code than P1963 set?

	Inspection chart for diagnosis code (Refer to ).

	Go to Step 2 .

STEP 2. M.U.T.-III data list

Refer to Data List Reference Table .

Item No. 80: Air flow sensor

Q. Is the check result normal?

	Go to Step 3 .

	Check air flow sensor system (Refer to Code No. P0100 ).

STEP 3. Check air intake from intake hose and inlet manifold.

Q. Is the check result normal?

	Go to Step 4 .

	Repair.

STEP 4. Check supercharging pressure.

Check supercharging pressure (Refer to GROUP 15 - On-vehicle Service - Turbocharger Supercharging Pressure Check <4G1> ).

Q. Is the check result normal?

	Go to Step 5 .

	Repair.

STEP 5. Check supercharging pressure control system.

Check supercharging pressure control system (Refer to GROUP 15 - On-vehicle Service - Supercharging Pressure Control System Check <4G1> ).

Q. Is the check result normal?

	Go to Step 6 .

	Repair.

STEP 6. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Q. Is diagnosis code set?

	Replace the engine-ECU.

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