Code No.B1201: Fuel information error


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












TROUBLE JUDGMENT



PROBABLE CAUSES



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

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-22 fuel pump and gauge unit (main) and D-24 fuel gauge unit (sub) <4WD only> connector

Q. Is the check result normal?
Go to Step 2.
Repair the connector, and then go to Step 9.

STEP 2. Fuel pump and gauge unit (main) and fuel gauge unit (sub) <4WD only> check
Check the Fuel pump and gauge unit (main) and fuel gauge unit (sub) <4WD only>. Refer to .

Q. Is the check result normal?
Go to Step 3.
Replace the Fuel pump and gauge unit (main) and fuel gauge unit (sub) <4WD only>.

STEP 3. Check of fuel gauge (main) circuit
(1)Disconnect the D-22 fuel pump and fuel 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?
Go to Step 8.
Go to Step 4.

STEP 4. Resistance measurement at the D-22 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-22 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?
Go to Step 6.
Go to Step 5.

STEP 5. Check the wiring harness between the D-22 fuel pump and gauge unit (main) connector terminal No. 1 and the body earth.

Q. Is the check result normal?
Go to Step 9.
Repair the wiring harness, and then go to Step 9.

STEP 6. Connector check: C-03 combination meter connector

Q. Is the check result normal?
Go to Step 7.
Repair the connector, and then go to Step 9.

STEP 7. Check the wiring harness between the C-03 combination meter connector terminal No. 18 and the D-22 fuel pump and gauge unit (main) connector terminal No. 2
note Before the wiring harness check, check the intermediate connectors C-35 and D-05, and repair them if necessary.

Q. Is the check result normal?
Go to Step 8.
Repair the wiring harness, and then go to Step 9.

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

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

Q. Is the check result normal?
Go to Step 9.
Replace the combination meter

STEP 9. Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the combination meter.
(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?
Replace the combination meter
The diagnosis is complete.