Circuit Inspection

INSPECTION PROCEDURE

1. Inspect indicator. 

   Check:  Turn ON and OFF the switch corresponding to the following indicators and check if the indicator lights up or goes off accordingly.

   • Door indicator (Open/close operation of any of doors)
   • Brake indicator (ON/OFF operation of the parking brake)
   • Seat belt indicator (ON/OFF operation of the buckle switch)
   1. Yes:  Normal communication.
   2. No: Go to   2 . 
2. Any of them do not light. 
   1. NO:  Go to  3.
   2. Yes:  Flow chart No.  5.
3. All of them do not light. 

   Communication error. Wire harness faulty. 

INSPECTION PROCEDURE

1. Check the meter operation. 

   Check:  With the ignition switch ON, nothing is displayed.

2. Check the positive terminal of IG. 

   CHECK:  if the fuse (GAUGE 10A) is normal or not. Turn the ignition switch ON and check that a voltage of 10 - 14 V is applied between the meter connector terminal A22 (IG+) and the body ground.

   1. Yes:  Go to  3.
   2. No:  Fuse faulty. Wire harness faulty.
3. Check the grounding. 

   Check:  Disconnect the meter connector and check that there is continuity between terminal A15/A14 on the vehicle side connector and the body ground.

   1. Yes:  Improper connection of the meter connector. Communication meter ECU faulty.
   2. No:  Body ground faulty. Wire harness faulty.

INSPECTION PROCEDURE

1. Check the brake ECU. 

   CHECK:

   1. Perform a diagnosis check of the brake system.
   2. Proceed to next Circuit inspection shown in problem symptoms table. See TROUBLE SHOOTING .
   1. No:  Go to  2.
   2. Yes:  Replace brake ECU.
2. Check the vehicle speed signal input. 

   Preparation:  Turn the ignition switch ON.

   CHECK:  Disconnect the meter connector, drive the vehicle at a speed of 2 - 4 km/h and check that continuity between terminal A9 on the vehicle side connector and the body ground is repeatedly turned ON and OFF.

   1. Yes:  Combination meter ECU faulty.
   2. No:  Wire harness faulty. Speed output terminal in brake ECU faulty.

INSPECTION PROCEDURE

1. Fuel gauge diagnosis check  . See Fuel gauge .
2. Reset inclination sensor  . See RESET INCLINATION SENSOR .
3. Fuel sender gauge check  . See STEP 1 - INSPECT COMBINATION METER CIRCUIT .
   1. NG:  Replace fuel tank.
   2. OK:  Go to  4.
4. Multiplex communication Circuit check  . See HOW TO PROCEED WITH TROUBLESHOOTING MULTIPLEX COMMUNICATION SYSTEM .

   CHECK:  if the communication between the combination meter and the multiplex communication Circuit is normal or not.

   1. No:  Multiplex communication Circuit error. Wire harness faulty.
   2. Yes:  Go to  5.
5. Check the body ECU. 

   CHECK:  with the fuel sender gauge connector connected, check if the voltage between each of terminal 1 (FV), 5 (FR) and 6 (FE) of the vehicle side wire harness and connector and the body ground is normal or not.

   Fig 1: Identifying Fuel Sender Gauge Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 2: Fuel Sender Gauge Terminal Specifications

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. No:  Body ECU faulty.
   2. Yes:  Combination meter ECU faulty.

Inspection procedure

1. Multiplex communication Circuit input indicator or warning. 
2. Communication check. 

   CHECK:  if the communication between the combination meter and the multiplex communication Circuit is normal or not.

   1. Yes:  Go to  3.
   2. No:  Communication error. Wire harness faulty.
3. Check the bulb or Circuit plate. 

   CHECK:  if the bulb Circuit plate is normal or not. Check open or short Circuit in wire harness.

   1. Yes:  Go to  4.
   2. No:  Bulb or Circuit plate faulty.
4. Check the corresponding switch or ECU. 

   CHECK:  if the corresponding switch or ECU is normal or not.

   1. Yes:  Combination meter ECU faulty.
      Fig 3: Identifying Multiplex/Single Communications Inputs

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. No:  Corresponding switch or ECU faulty.