B1312

DTC B1312 Time-out error (TN panel open)






CIRCUIT OPERATION

At opening or closing operation, when the tonneau latch is opened, the convertible top control module applies current to the solenoid valve (tonneau drive cylinder) to control the hydraulic pressure to the tonneau drive cylinder. As a result, the tonneau panel is opened.
Then, when the tonneau sensor is turned ON, this control is terminated.

DTC SET CONDITION

This DTC is set when the tonneau sensor signal is not turned ON after the operation above continues for approximately ten seconds.

TROUBLESHOOTING HINTS

- OFF failure of the tonneau sensor
- Malfunction of the solenoid valve (tonneau drive cylinder)
- Damaged harness wires and connectors
- Malfunction of hydraulic circuit
- Malfunction of the convertible top control module

DIAGNOSIS

Required Special Tool

- MB991958 Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827 M.U.T.-III USB Cable
- MB991910 M.U.T.-III Main Harness A
- MB992006: Extra fine probe

STEP 1. Check the convertible top operation.

When the convertible top is opened, check that the tonneau panel rises and stops in approximately 4 seconds.

Q. Does the tonneau panel rise when the convertible top is opened?

YES (stops in approximately 4 seconds.) : Replace the tonneau open sensor. Then go to Step 7.
YES (stops in approximately 10 seconds.) : If it takes approximately 10 seconds to stop, the operation is stopped by the convertible top control module fail-safe function. In this case, the hydraulic circuit may be defective.
Check the hydraulic circuit.
NO : Go to Step 2.
STEP 2. Check convertible top control module connector F-27 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q. Is the check result satisfactory?

YES Go to Step 3.

NO Repair or replace the damaged component(s).

STEP 3. Measure the resistance at convertible top control module connector F-27.





(1)Disconnect convertible top control module connector F-27, and measure at the wiring harness side.





(2)Measure the resistance between terminal 7 and 5.

- The measured value should be 5 - 7ohms .

Q. Is the check result satisfactory?

YES Go to Step 6.

NO Go to Step 4.

STEP 4. Check solenoid valve (tonneau drive cylinder) connector F-17 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q. Is the check result satisfactory?

YES Go to Step 5.

NO Repair or replace the damaged component(s).

STEP 5. Solenoid valve (tonneau drive cylinder) check

Check that the resistance value of the solenoid valve (tonneau drive cylinder) is within the standard value range.

Standard value: 5 - 7ohms


Q. Is the check result satisfactory?

YES Check the harness between convertible top control module connector F-27 (terminal 7, 5) and solenoid valve (tonneau drive cylinder) connector F-17 (terminal 1, 2). Repair as necessary.
NO Replace the solenoid valve (tonneau drive cylinder).
STEP 6. Hydraulic circuit check

Check the hydraulic circuit to the tonneau drive cylinder.

Q. Is the check result satisfactory?

YES Replace the convertible top control module.
NO Repair or replace the damaged component(s).
STEP 7. Recheck the DTC.

Q. Is DTC B1312 set?

YES Replace the convertible top control module.
NO This diagnosis is complete.