Checking mechanical shift valves
- The STC/DSTC function is disengaged
- The car is raised so that the drive wheels are clear of the ground.WARNING:
Ensure that the car is safely raised.
WARNING:Check that there are no objects caught in the front tire treads.
- Start the engine
- Read off the gear ratio during shifting.
Move the gear shift selector to position 1. Accelerate carefully until the engine speed (RPM) is approximately 2000 RPM.
Try to maintain a constant engine speed throughout the test.
NOTE:The gear ratio varies if a constant vehicle speed and engine speed (RPM) are not maintained. This is because the transmission will free wheel.
Then move the gear selector to position 2 within 10 seconds, to position 3 within a further 10 seconds and then to position D (fourth gear).
Check that the shifts are carried out correctly by comparing the gear ratios with Table 1 - Valve stuck when up-shifting .
Then move the gear selector from position D to position 3 within 10 seconds, to position 2 within a further 10 seconds and then to position 1.
Check that the shifts are carried out correctly by comparing the gear ratios with Table 2 - Valve stuck when down-shifting .
Gear ratios Gear Gear ratios Gear ratio (S80 (-06) turbo) Gear ratio (S80 (-06) non-turbo, XC90) 1 3.275 2 1.758 3 1.121 4 0.790 Table 1 - The valve has stuck during up-shifting Mechanical shift valve Shift pattern Corrective action Valve 1-2 has stuck 2 - 2 - 3 - 4 Replacing the control system Valve 2-3 has stuck 1 - 3 - 3 - 4 Replacing the control system Valve 2-3 has stuck 3 - 3 - 3 - 4 Replacing the control system Valve 3-4 has stuck 1 - 2 - 4 - 4 Replacing the control system Table 2 - The valve has stuck during down-shifting Mechanical shift valve Shift pattern Corrective action Valve 1-2 has stuck 1 - 1 - 3 - 4 Replacing the control system Valve 2-3 has stuck 1 - 2 - 2 - 2 Replacing the control system Valve 2-3 stuck (or internal fault in the transmission) 1 - 2 - 2 - 4 Checking engine braking Valve 3-4 has stuck 1 - 2 - 3 - 3 Replacing the transmission NOTE:Diagnostic trouble codes (DTCs) may be stored in the ABS system when the rear wheels are stationary and the front wheels rotate. Erase any diagnostic trouble codes (DTCs) stored in the ABS system after fault-tracing.
Other information:
- To replace the control system, see Control system/valve housing, removing for removal. See Installing the control system / valve housing for installation.
Select an alternative
- The control system has been replaced
Refer to Resetting the adaptation
- Shift valve 2-3 has stuck in shift pattern 1-2-2-4 according to table 2
Refer to Checking engine braking
- Shift valve 3-4 has stuck according to table 2
- There is no incorrect shift pattern.
Refer to Replacing the transmission