Inspection Procedure

HINT:

Read freeze frame data using OBD II scan tool or hand-held tester. Because freeze frame records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

1. Connect OBD II scan tool or hand-held tester, and read value of mass air flow rate. 

   PREPARATION: 

   1. Connect the OBD II scan tool or hand-held tester to the DLC3.
   2. Turn the ignition switch ON and push the OBD II scan tool or hand-held tester main switch ON.
   3. Start the engine.

   CHECK: 

   Read the mass air flow rate on the OBD II scan tool or hand-held tester.

   RESULT: 

   RESULT CHART
   
   

   -	Type I	Type II
   Mass Air Flow Rate (gm/sec.)	0.0	271.0 or more

   1. Type II: Go to Step   5 . 
   2. Type I: Go to next step. 
2. Check voltage of mass air flow meter power source. 

   PREPARATION: 

   1. Disconnect the mass air flow meter connector.
   2. Turn the ignition switch ON.

   CHECK: 

   Measure the voltage between terminal 1 of the mass air flow meter connector and body ground.

   OK: 

   Voltage: 9-14 V 

   Fig 1: Checking Voltage Of Mass Air Flow Meter Power Source

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: Check for open in harness and connector between EFI relay (Marking: EFI) and mass air flow meter (See  PROCEDURE  ).  
   2. OK: Go to next step. 
3. Check voltage between terminal VG of ECM connector and body ground. 

   PREPARATION: 

   1. Remove the glove compartment (See ENGINE CONTROL MODULE (ECM) ).
   2. Start the engine.

   CHECK: 

   Measure the voltage between terminal VG of the ECM connector and body ground while the engine is idling.

   OK: 

   Voltage: 

   1.1 - 1.5 V (P or N position and A/C switch OFF) 

   Fig 2: Checking Voltage Terminal VG Of ECM Connector & Body Ground

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. OK: Check and replace ECM (See  PROCEDURE  ).  
   2. NG: Go to next step. 
4. Check for open and short in harness and connector between mass air flow meter and ECM (See  PROCEDURE  ).  
   1. NG: Repair or replace harness or connector. 
   2. OK: Replace mass air flow meter. 
5. Check continuity between terminal E2G of ECM connector and body ground. 

   PREPARATION: 

   Remove the glove compartment (See ENGINE CONTROL MODULE (ECM) ).

   CHECK: 

   Check the continuity between terminal E2G of the ECM connector and body ground.

   OK: 

   Continuity (1 Ω or less) 

   Fig 3: Checking Terminal E2G Of ECM Connector & Body Ground

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG: Check and replace ECM (See  PROCEDURE  ) 
   2. OK: Go to next step. 
6. Check for open in harness and connector between mass air flow meter and ECM (See  PROCEDURE  ). 
   1. NG: Repair or replace harness or connector. 
   2. OK: Replace mass air flow meter.