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B2433. B2434

Symptom: TCS OFF lamp on, TCS symptom inoperative

B2433. B2434

TCS throttle motor shorted to ground/battery +, no continuity or mechanical fault


Fault symptom

TCS OFF lamp on, TCS symptom inoperative

Condition

B2433: Control module output pin 18 shorted to ground, battery + or pin 35.

Control module output pin 35 shorted to ground, battery + or pin 18.

B2434: Control module output pin 18, no continuity.

Control module output pin 35, no continuity.

Control module input pin 27, no continuity.

Throttle butterfly mechanism or motor binding.

Note

B2434 is generated when the butterfly's "ACTUAL" value does not coincide with its "REFERENCE" value. This means that the butterfly cannot assume a position calculated by the control module or that the control module cannot calculate the position of the butterfly. This could be due to any of three reasons:



• A mechanical fault, such as a binding throttle butterfly.

• An electrical fault, such as a break in the wiring, which prevents the throttle motor from working.

• No information received by the control module from the throttle body about the position of the butterfly, such as no continuity on pin 27 of the control module input.

B2434 can be generated in connection with fault diagnosis when the throttle body wiring is disconnected and the ignition switch is turned to the Drive position.


Diagnostic procedure - B2433


1. With the ignition switched off, unplug connector H16-2 and check that the engine is not shorted to ground by measuring the resistance across ground and pin 7 of the female connector and also across ground and pin 8 of the female connector.

In both cases the resistance should be infinite (OL).


Important

The throttle motor must never be supplied directly with 12 V.


2. Check the throttle motor electrically and mechanically by connecting it to the car battery in series with the high- beam filament of a 12V/60W bulb (H4). Using a multimeter set for measuring current in the 10A range, a reading of 3.8 ± 0.5 A should be obtained. Slowly change the position of the butterfly by hand from open to closed. The meter reading should now vary by a maximum of ± 0.5 A from the reading first obtained.

Also check that it is noticeably harder to close the butterfly when the throttle motor is supplied with current.

If the above checks out OK, proceed to point 4. If not, continue with point 3.

3. Remove the TCS throttle body.


Repeat the checking procedure described in points 1 and 2, but now directly on pins 1 and 5 of the throttle motor.

If the readings obtained are correct, remedy the faulty wiring between the throttle motor and connector H16-2.

If incorrect readings are also obtained here, fit a replacement TCS throttle body.




4. With the ignition switched off, plug a BOB into the TCS control module connector (control module not connected). Check the cable between pin 18 of the control module connector and pin 8 of the male connector (H16-2) for continuity/shorting.


Also check the cable between pin 35 of the control module connector and pin 7 of the male connector for continuity/shorting.

5. Clear the code diagnostic trouble code. Start the car and drive it on test to check whether the diagnostic trouble code recurs. If it does, see "Before replacing a control module" for further measures.



Diagnostic procedure - B2434


1. With the ignition switched off, check that the throttle butterfly can easily be moved to the closed position by hand and that no binding occurs. The force of the spring should also return it to the open position with ease. If it is in proper working order, proceed to point 2. If it is not, remedy the fault if possible or fit a replacement throttle body.


2. Connect the ISAT. With the ignition in the Drive position, open the TCS throttle butterfly halfway by hand. Then select "BUTTERFLY CLOSING ON" in the "ACTIVATE" menu.


Note

If the actuator motor rotates the TCS throttle butterfly towards the open position when "BUTTERFLY CLOSING ON" is activated, it is because the control module receives no information about the position of the butterfly on input pin 27.

If the butterfly either closes or opens, proceed to point 4. If it does not, continue with point 3.


3. Carry out the measures described under diagnostic trouble code B2433.

4. Carry out the measures described under diagnostic trouble codes B1302 and B1303.