MECHANISM-BRAKE TRANSMISSION SHIFT INTERLOCK
DESCRIPTION
The
Brake
Transmission
Shifter/Ignition
Interlock
(BTSI) is a cable operated system that prevents the
transmission gear shifter from being moved out of
PARK without the proper driver inputs. The system
also contains a solenoid that is integral to the shifter
assembly. The solenoid works in conjunction with the
park lock cable to permit shifter movement out of
PARK when the brake is depressed.
A BTSI override (2) is provided on the side of the
shifter mechanism (1) to allow the vehicle to be shifted
out of PARK in the event of an electrical failure.
OPERATION
The
Brake
Transmission
Shifter/Ignition
Interlock
(BTSI) is engaged whenever the ignition switch is in
the LOCK (1) position. An additional electrically acti-
vated feature will prevent shifting out of the PARK
position unless the brake pedal is depressed at least
one-half inch. A solenoid in the shifter assembly is
energized when the brake pedal is depressed. When
the key is in the ON position and the brake pedal is
depressed, the shifter is unlocked and will move into
any position. The interlock system also prevents the
ignition switch from being turned to the LOCK position,
unless the shifter is in the gated PARK position.
The following chart describes the normal operation of the Brake Transmission Shift Interlock (BTSI) system. If the
“expected response” differs from the vehicle’s response, then system repair and/or adjustment is necessary.
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AUTOMATIC TRANSMISSION 42RLE - SERVICE INFORMATION
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