Inspection Procedure

Hand-held tester: 

1. Connect hand-held tester and check operation of fuel pump (See  PRE-CHECK   ). 
   • OK: Proceed to next circuit inspection shown in problem symptoms table (See  PROBLEM SYMPTOMS TABLE   ). 
   • NG: Go to next step. 
2. Check for ECM power source circuit (See  ECM POWER SOURCE CIRCUIT   ). 
   • NG: Repair or replace. 
   • OK: Go to next step. 
3. Check circuit opening relay (Marking: C/OPN) (See  INSPECTION  ). 
   • NG: Replace circuit opening relay. 
   • OK: Go to next step. 
4. Check voltage between terminal FC of ECM and body ground. 

   PREPARATION: 

   1. Turn the ignition switch to ON.

   CHECK: 

   Measure the voltage between the terminal FC of the ECM and body ground.

   OK: Voltage: 9 to 14 V 

   Fig 1: Checking Voltage Between Terminal FC And Body Ground

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • OK: Go to step 5. 
   • NG: Check for open in harness and connectors between ignition switch and circuit opening relay (Marking: C/OPN), circuit opening relay and ECM (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
5. Check fuel pump (See  FUEL PUMP  ). 
   • NG: Repair or replace fuel pump. 
   • OK: Go to next step. 
6. Check for open in harness and connectors between circuit opening relay and fuel pump and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
   • NG: Repair or replace harness or connector. 
   • OK: Replace ECM (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 

OBD II scan tool (excluding the hand-held tester): 

1. Check operation of fuel pump. 

   PREPARATION: 

   1. Turn the ignition switch to ON.

   CHECK: 

   1. Connect between the terminal FC of the ECM connector and body ground.
   2. Check for fuel pressure in the fuel inlet hose when it is pinched off.

   OK: 

   There is pressure in fuel inlet hose. 

   HINT:

   At this time, you will hear a fuel return flowing noise.

   Fig 2: Checking Fuel Pump Operation

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   • OK: Proceed to next circuit inspection shown in problem symptoms table (See  PROBLEM SYMPTOMS TABLE   ). 
   • NG: Go to next step. 
2. Check for ECM power source circuit (See  ECM POWER SOURCE CIRCUIT   ). 
   • NG: Repair or replace. 
   • OK: Go to next step. 
3. Check circuit opening relay (Marking: C/OPN) (See  INSPECTION  ). 
   • NG: Replace circuit opening relay. 
   • OK: Go to next step. 
4. Check voltage between terminal FC of ECM and body ground (See   4  in INSPECTION PROCEDURE).  
   • OK: Go to step 5. 
   • NG: Check for open in harness and connectors between ignition switch and circuit opening relay (Marking: C/OPN), circuit opening relay and ECM (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
5. Check fuel pump (See  FUEL PUMP  ). 
   • NG: Repair or replace fuel pump. 
   • OK: Go to next step. 
6. Check for open in harness and connectors between circuit opening relay and fuel pump and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
   • NG: Repair or replace harness or connector. 
   • OK: Replace ECM (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ).