Code No.B1201: Fuel information error


caution Whenever the ECU is replaced, ensure that the communication circuit is normal.

TROUBLE JUDGEMENT



PROBABLE CAUSES



  • Damaged harness wires and connectors
  • Malfunction of fuel pump and gauge unit (main)
  • Malfunction of fuel gauge unit (sub) <4WD>
  • Malfunction of combination meter

DIAGNOSIS PROCEDURE


STEP 1. Connector check: D-24 fuel pump and gauge unit (main) and D-25 fuel gauge unit (sub) <4WD> connector


Q. Is the check result normal?





STEP 2. fuel pump and gauge unit (main) and fuel gauge unit (sub) <4WD> check



Q. Is the check result normal?





STEP 3. Check of fuel pump and gauge unit (main) circuit


(1)Disconnect the D-24 fuel pump and gauge unit (main) connector.
(2)Use the special tool Check harness (MB991219) to connect a test lamp (12 V - 3.4 W) between the wiring harness connector terminals 1 and 2.
(3)Turn the ignition switch to the ON position.
(4)Check if the test lamp illuminates.
OK: Illuminates

Q. Is the check result normal?





STEP 4. Resistance measurement at the D-24 fuel pump and gauge unit (main) connector


(1)Disconnect the fuel pump and gauge unit (main) connector, the measure at the harness side.
(2)Measure the resistance between the D-24 fuel pump and gauge unit (main) connector terminal No. 1 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?





STEP 5. Check the wiring harness between the D-24 fuel pump and gauge unit (main) connector terminal No. 1 and the body earth.



Q. Is the check result normal?





STEP 6. Connector check: C-203 combination meter connector


Q. Is the check result normal?





STEP 7. Check the wiring harness between the C-203 combination meter connector terminal No. 18 and the D-24 fuel pump and gauge unit (main) connector terminal No. 2



note Before the wiring harness check, check the intermediate connectors C-17, D-30 <2WD> and D-31 <4WD>, and repair them if necessary.

Q. Is the check result normal?





STEP 8. M.U.T.-III actuator test



  • Item 03: Fuel tank gauge (target value): 0 →100%
OK: The fuel tank gauge operates.

Q. Is the check result normal?





STEP 9. Check whether the diagnosis code is reset.



(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?