Test Mode 3: Testing Output Signals

Test mode 3: Testing output signals

The output signals to the control system components are tested in test mode 3. The test is performed in a cycle in which each component is activated 6 times with a brief interval between each activation and a longer interval between each component. This cycle is performed three times, following which test mode 3 is terminated automatically.
The gear selector lever must be in position P or N and the car must be at rest before test mode 3 can function. Thus, test mode 3 cannot be used while driving. The following list specifies the order of testing.

Operation is verified by observing or listening to the activated component. The idling speed is increased when the drive compensation function is activated and reduced in response to torque reduction.

If any signal is absent, troubleshooting should be carried out on the circuit of which the component is part.

Testing is carried out as follows:

- The gear selector lever must be in position P or N.
- The vehicle speed must be 0. In other words, the test cannot be carried out while driving.
- Switch off ignition.
- Start engine and allow to idle.





Testing output signals with Volvo ST

- Search for text MODE 3: CYCL. ACT. Press * using arrow keys.
- Press * for activation.

ST key indicates order in which components will be operated.





Testing output signals manually

- Press DLC test button three times.

LED will commence to flash in step with activation of components.

Order of operation

Observe flashing of LED on DLC.
Use stethoscope to detect clicking of solenoids.

1 Solenoid S1 operates: clicking sound from transmission
2 Solenoid S2 operates; clicking sound from transmission
3 Solenoid SL operates; clicking sound from transmission
4 Solenoid STH operates; clicking sound from transmission
5 Indicating lamp on combined instrument flashes
6 (Longer pause occurs at this point as spare output is tested.)
7 Drive compensation at idling
8 Torque reduction signal TC2 at idling
9 Torque reduction signal TC1 at idling

Note!
Change in idling speed will be heard in tests 7, 8 and 9.