Manual Shifting Test

NOTE: This test determines if a problem is related to a mechanical or electrical component.

Stop the engine and disconnect the TCU or the TCU fuse.

Road test the vehicle. Shift the transmission manually into each gear range. The transmission should operate as follows:


Lock in Park

Back up in Reverse

Not move in Neutral

Provide first gear only with shift lever in 1-2 position

Operate in third gear only with shift lever in 3 position

Operate in overdrive fourth gear only with shift lever in D position

If the transmission operates as described, proceed to the next test step. However, if the forward gear ranges were difficult to distinguish (all feel the same), or the vehicle would not back up, refer to the diagnosis charts. Do not perform the stall or time lag tests.


CAUTION: Do not overspeed the engine during the next test step. Ease off the throttle and allow the vehicle to slow before downshifting.

Continue the road test. Manually downshift the transmission from D to 3, and from 3 to the 1-2 position. Then manually upshift the transmission through the forward ranges again.

If transmission operation is OK, perform the stall, time lag and pressure tests. If a transmission shifting problem is encountered, refer to the diagnosis charts

If a problem still exists, continue testing with the MS 1700 tester.