Code No.B1201:
Fuel information problem
caution |
Before replacing the combination
meter, ensure that the power supply circuit, the earth circuit and the communication circuit
are normal.
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TROUBLE JUDGEMENT
With the ignition switch at the ON position and the diagnosis code No. U1190 is not stored,
if the combination meter detects the abnormal resistance of fuel level sensor circuit for 64
seconds continuously, the diagnosis code No. B1201 is stored.
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. Check of fuel pump and gauge unit (main) circuit
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(1)Disconnect the fuel pump and gauge unit (main) connector.
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(2)Use the special tool Check harness (MB991219) to connect a test lamp (12 V - 3.4
W) between the wiring harness connector terminals.
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(3)Turn the ignition switch to the ON position.
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(4)Check if the test lamp illuminates. OK: Illuminates
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Q.
Is the check result normal?
Go to Step 6.
Go to Step 2.
STEP 2. Fuel pump and gauge unit (main) and fuel gauge unit (sub)
check
Check the fuel pump and gauge unit (main) and fuel gauge unit (sub). 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).
STEP 3. Resistance measurement at the fuel pump and gauge unit (main)
connector
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(1)Disconnect the fuel pump and gauge unit (main) connector, the measure at the harness
side.
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(2)Measure the resistance between the fuel pump and gauge unit (main) connector (earth
terminal) and the body earth. OK: Continuity exists (2 Ω or less)
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Q.
Is the check result normal?
Go to Step 5.
Go to Step 4.
STEP 4. Check of open circuit (disconnect) in body earth line between
fuel pump and gauge unit (main) connector and body earth.
Q.
Is the check result normal?
Go to Step 7.
Repair the connector(s) or wiring harness, and then go to Step 7.
STEP 5. Check of short to power supply circuit (connect) in F/G line
between combination meter connector and fuel pump and gauge unit (main) connector.
Q.
Is the check result normal?
Go to Step 6.
Repair the connector(s) or wiring harness, and then go to Step 7.
STEP 6. 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 7.
Replace the combination meter.
STEP 7. Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the combination meter.
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(1)Erase the diagnosis code.
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(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
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(3)Check if diagnosis code is set.
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Q.
Is the diagnosis code set?
Replace the combination meter.
The diagnosis is complete.