Code 86, Shift Solenoid "B" Stuck "On": Notes

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The shift solenoids are used inside the valve body to control spool valves, which determine the transmission gear. Fused ignition power is supplied to solenoid "B". The PCM/TCM will engage solenoid "B" by grounding circuit No. 1223 to energize the solenoid.

Code 86 will set under the following conditions.

Vehicle speed is greater than 7 MPH.
TPS is more than 25 percent.
PCM/TCM commands 1st or 2nd gear.
Transmission ratio indicates transmission is in 3rd or 4th gear.
Conditions are met for 6 seconds.
NOTE: Test numbers refer to test numbers on diagnostic chart.

This test determines if transmission is receiving a solenoid "B" on command.