DTC B2274: ACC Monitor Malfunction: Procedure

1. Connect Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn Techstream main switch on.
3. Read the Data List according to the displays on the tester.

   HINT: 

   When using Techstream with the engine switch off, turn on and off any of the door courtesy light switches repeatedly at 1.5 second intervals or less until communication between the tester and vehicle starts.

   MAIN BODY:
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   ACC Relay Mon	Status of ACC Relay Monitor / ON or OFF	ON: Engine switch on (ACC) OFF: Engine switch off	-

   OK

   "ON" (engine switch on (ACC) appears on the screen.

NG → See step   4 

OK: Go to next step 

1. Check the power source mode changes.
   1. When the key is inside the vehicle and the shift lever is in the P position, check that pressing the engine switch causes the power source mode to change as follows:

      OK

      off → on (ACC) → on (IG) → off

NG → See step   7 

OK: Go to next step 

1. Delete the DTCs, refer to DTC CHECK / CLEAR .
2. Check for DTCs again.

   OK

   No DTC is output.

NG → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK) 

OK → See step   8 

1. Remove the ACC relay from the instrument panel junction block
   Fig 1: Identifying ST CUT Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   3 - 5	When battery voltage is not applied to terminals 1 and 2	10 kΩ or higher
   3 - 5	When battery voltage is applied to terminals 1 and 2	Below 1 Ω

NG → REPLACE ACC RELAY 

OK: Go to next step 

1. Disconnect the D8 connector from the main body ECU (instrument panel junction block).
   Fig 2: Identifying D8 Main Body ECU (Instrument Panel Junction Block) Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the 1I connector from the instrument panel junction block.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   1I-3 - D8-22 (ACCD)	Always	Below 1 Ω
   D8-22 (ACCD) or 1I-3 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU - INSTRUMENT PANEL JUNCTION BLOCK) 

OK: Go to next step 

1. Disconnect the 1A and 1F connectors from the instrument panel junction block.
   Fig 3: Identifying 1A And 1F Instrument Panel Junction Block Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   1F-10 - Body ground	Always	Below 1 Ω

3. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Condition	Specified Condition
   1A-1 - Body ground	Always	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK)