3-2 Control Solenoid Circuit Check: Notes

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The 3-2 control solenoid hydraulically coordinates the apply rate of the 2-4 band with hydraulic release of the 3-4 clutch during a 3-2 downshift. The 3-2 circuit duty cycle is continually monitored by PCM depending on command state of circuit. When transmission is in 1st gear, duty cycle of solenoid is equal to zero. When transmission is in 2nd gear or higher, duty cycle of solenoid will be about 90 percent. When transmission downshifts 3-2, duty cycle of solenoid will be about 20 percent.

For example, if PCM commands solenoid on, duty cycle on that circuit should drop when solenoid is grounded. If voltage stays up for 4 seconds, a code will set. If 3-2 control solenoid is off, duty cycle on circuit should remain high. If voltage drops for 4 seconds, a code will set. When code is set, a soft landing to 3rd gear will occur.

NOTE: Test numbers refer to numbers on diagnostic chart.

This test check 3-2 control solenoid and internal transmission harness for short circuits.
This test checks for power, from the ignition through the fuse, to the 3-2 control solenoid.
This test ensures circuit No. 897 is not shorted to ground.
This test checks ability of PCM to ground or control 3-2 control solenoid. If bidirectional scan tester is not available, solenoid may be activated by grounding ALDL test terminal "B" with ignition on and engine off.