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For 1990-2009 cars only

Automatic Transmission Shift Lock Control Inoperative Does Not Shift Out of PARK

Step

Action

Value(s)

Yes

No

1

Was the Brake Transmission Shift Interlock System Check performed?

--

Go to Step  2

Go to Automatic Transmission Shift Lock Control System Check

2

  1. Check for any mechanical binding or foreign material that may prevent the BTSI from operating properly.
  2. Disconnect inline connector C205.
  3. Turn the ignition switch to the ON position.
  4. Press the brake pedal.
  5. Use a DMM in order to measure the voltage between terminal 8 of the female side of inline connector C205 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  4

Go to Step  3

3

  1. Inspect fuse 2. Replace the fuse if it is open.
  2. Locate an open or a high resistance in any of the following circuits:
  3. • CKT X11
    • CKT FX102
    • CKT FX900
  4. Repair any open or high resistance in these CKTs.
  5. If these CKTs are OK, replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Brakes.

Is the repair or replacement complete?

--

Go to Step  9

--

4

Use the DMM in order to measure the resistance between terminal 6 of the female side of inline connector C205 and ground.

Does the resistance measure within the specified range?

Less than 5 ohms

Go to Step  6

Go to Step  5

5

  1. Locate an open or a high resistance in CKT F950.
  2. Repair the open or the high resistance in CKT F950.

Is the repair complete?

--

Go to Step  9

--

6

Use the DMM to measure the resistance between terminal 6 of the male side of connector C205 and terminal 7 of the male side of connector C205.

Does the resistance measure within the specified range?

Less than 5 ohms

Go to Step  7

Go to Step  8

7

  1. Locate for an open or a high resistance in circuit B930 or the diode in that circuit .
  2. Repair the open or a high resistance circuit B930 or replace the diode in that circuit.
  3. If these circuits are OK, replace the automatic transmission shift lock control solenoid.

--

Go to Step  9

--

8

  1. Locate an open or a high resistance in circuits X950, X920, M910 or M940.
  2. Repair the open or a high resistance circuit X950, X920, M910 or M940.
  3. If these circuits are OK, replace the automatic transmission shift lock control switch.

--

Go to Step  9

--

9

  1. Reconnect all of the connectors and the components that were disconnected.
  2. Verify that the transmission will shift out of the PARK position when the brake pedal is pressed.

Will the transmission shift out of the PARK position when the brake pedal is pressed?

--

Go to Automatic Transmission Shift Lock Control System Check

Go to Step  1

Automatic Transmission Shift Lock Control Inoperative Trans Shifts Out of PARK

Step

Action

Value(s)

Yes

No

1

Was the Brake Transmission Shift Interlock System Check performed?

--

Go to Step  2

Go to Automatic Transmission Shift Lock Control System Check

2

  1. Inspect the system for any mechanical binding or foreign material that may prohibit the BTSI from operating properly.
  2. Disconnect inline connector C205.
  3. Turn the ignition switch to the ON position.
  4. Use a DMM in order to measure the voltage between terminal 8 of the female side of inline connector C205 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  4

Go to Step  3

3

Check the integrity of the automatic transmission shift lock control solenoid. Replace the automatic transmission shift lock control solenoid if it is damaged or if it does not operate properly.

Is the repair complete?

--

Go to Step  9

--

4

  1. Disconnect the stop lamp switch.
  2. Use the DMM in order to measure the voltage between terminal 8 of the female side of inline connector C205 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  6

Go to Step  5

5

Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Brakes.

Is the repair complete?

--

Go to Step  9

--

6

  1. Disconnect the Body Control Module (BCM) connector C2.
  2. Use the DMM in order to measure the voltage between terminal 8 of the female side of inline connector C205 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  8

Go to Step  7

7

Replace the BCM. Refer to Body Control Module Replacement

Is the repair complete?

--

Go to Step  9

--

8

  1. Locate a short to B+ in any of the following circuits:
  2. • CKT FX102
    • CKT FX900
    • CKT FX750
    • CKT FX899
  3. Repair any short to B+ in the CKTs.

Is the repair complete?

--

Go to Step  9

--

9

  1. Reconnect all of the connectors and all of the components that were disconnected.
  2. Verify that the transmission shifts out of the PARK position ONLY when the brake pedal is pressed.

Does the transmission shift out of the PARK position only when the brake pedal is pressed?

--

Go to Automatic Transmission Shift Lock Control System Check

Go to Step  1

Automatic Transmission Shift Lock Control Inoperative BTSI Indicator is Inoperative

Step

Action

Value(s)

Yes

No

1

Was the Brake Transmission Shift Interlock System Check performed?

--

Go to Step  2

Go to Automatic Transmission Shift Lock Control System Check

2

Determine if the BRAKE TO SHIFT indicator is inoperative or if it is on at all times.

Is the BRAKE TO SHIFT indicator inoperative?

--

Go to Step  3

Go to Step  11

3

  1. Turn the ignition switch to the ON position.
  2. Disconnect the BCM connector C2.
  3. Connect a fused jumper between terminal C15 of the BCM connector C2 and ground.

Does the BRAKE TO SHIFT indicator turn on?

--

Go to Step  4

Go to Step  5

4

  1. Place the transmission in the PARK position.
  2. Disconnect the BCM connector C1.
  3. Use a DMM to measure resistance between terminal B1 of the BCM connector C1 and ground.

Is the measured resistance within the specified value?

OL

Go to Step  8

Go to Step  7

5

  1. Replace the brake to shift indicator lamp.
  2. reconnect the fused jumper between terminal C15 of the BCM connector C2 and ground.

Does the BRAKE TO SHIFT indicator turn on?

--

Go to Step  17

Go to Step  6

6

  1. Locate an open or a high resistance in CKT FA825 and/or in CKT FA399.
  2. Repair the open or the high resistance in CKT FA825 and/or CKT FA399.
  3. If these CKTs are OK, replace the instrument cluster. Refer to Instrument Cluster Gage Replacement

Is the repair complete?

--

Go to Step  17

--

7

  1. Locate a short to ground in CKT B900 or P900.
  2. Repair the short to ground in CKT B900 or P900.
  3. If the CKT is OK , Replace the automatic shift lock control switch.

Is the repair complete?

--

Go to Step  17

--

8

Use a DMM in order to measure the voltage between terminal D11 of the BCM connector C2 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  9

Go to Step  10

9

  1. Locate a short to B+ in CKT FX102, FX899, FX750, FX900 or FB900.
  2. Repair the short to B+ in CKT FX102, FX899, FX750, FX900 or FB900.
  3. If the CKT is OK , Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement

Is the repair complete?

--

Go to Step  17

--

10

Replace the BCM. Refer to Body Control Module Replacement

Is the repair complete?

--

Go to Step  17

--

11

  1. Turn the ignition switch to the ON position.
  2. Disconnect the BCM connector C2.

Does the BRAKE TO SHIFT indicator turn off?

--

Go to Step  12

Go to Step  13

12

  1. Shift the transmission out of PARK position.
  2. Disconnect connector BCM connector C1.
  3. Use a DMM to measure resistance between terminal B1of the BCM connector C1 and ground.

Is the measured resistance within the specified value?

Less than 5 ohms

Go to Step  15

Go to Step  14

13

  1. Locate a short to ground in CKT FA825 and/or CKT FA399.
  2. Repair the short to ground in CKT FA825 and/or CKT FA399.
  3. If these CKTs are OK, replace the instrument cluster . Refer to Instrument Cluster Gage Replacement

Is the repair complete?

--

Go to Step  17

--

14

  1. Locate an open or high resistance in CKT B900 and/or CKT P900.
  2. Repair the open or high resistance in CKT B900 and/or CKT P900.
  3. If these CKTs are OK, replace the automatic transmission shift lock control switch.

Is the repair complete?

--

Go to Step  17

--

15

  1. Press the brake pedal.
  2. Use a DMM in order to measure the voltage between terminal D11 of the BCM connector C2 and ground.

Does the voltage measure at the specified value?

B+

Go to Step  16

Go to Step  10

16

  1. Locate an open or high resistances in CKT FX102, FX899, or FX750.
  2. Repair the open or high resistance in CKT FX102, FX899, or FX750.
  3. If the CKTs are OK , Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement

Is the repair complete?

Go to Step  17

17

  1. Reconnect all of the connectors and the components that were disconnected.
  2. Verify that the BRAKE TO SHIFT indicator operates properly.

Does the BRAKE TO SHIFT indicator operate properly?

--

Go to Automatic Transmission Shift Lock Control System Check

Go to Step  1