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Reverse Lockout System Inoperative

Reverse Lockout System Inoperative

Step Action Yes No
Schematic Reference:  Automatic Transmission Shift Lock Control Schematics  
Connector End View Reference:  Automatic Transmission Shift Lock Control Connector End Views   or  Body Control System Connector End Views  in Body Control System 
DEFINITION: Reverse shift lock control inoperative or always ON.
1 Did you perform A Diagnostic System Check - Automatic Transmission Shift Lock Control System? Go to Step 2  Go to Diagnostic System Check - Automatic Transmission Shift Lock Control 
2
  1. Turn ON the ignition, with the engine OFF.
  2. Press and hold the brake pedal.
  3. Attempt to move the shift lever into REVERSE.
Does the shift lever move to the REVERSE position?		 Go to Step 6  Go to Step 3 
3
  1. Turn OFF the ignition.
  2. Install a scan tool.
  3. Turn ON the ignition with the engine OFF.
  4. With a scan tool, observer the reverse lockout relay drive parameter in the dash integration module (DIM) data list.
Does the scan tool display an OFF status?		 Go to Step 4  Go to Step 17 
4
  1. Turn OFF the ignition.
  2. Disconnect the reverse lockout relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the shift lever into REVERSE.
Does the shift lever move to the REVERSE position?		 Go to Step 5  Go to Step 12 
5
  1. Turn OFF the ignition.
  2. Connect a test lamp between the reverse lockout relay coil side feed circuit and the reverse lockout relay control circuit.
  3. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 13  Go to Step 15 
6
  1. Turn OFF the ignition.
  2. Disconnect the reverse lockout relay.
  3. Connect the test lamp between the reverse lockout relay coil side feed circuit at the reverse relay connector and a good ground.
  4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 7  Go to Step 18 
7
  1. Turn OFF the ignition.
  2. Connect the test lamp between the reverse lockout relay switch side feed circuit at the reverse relay connector and a good ground.
  3. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 8  Go to Step 19 
8
  1. Turn OFF the ignition.
  2. Connect a test lamp between the reverse lockout relay coil side feed circuit and the reverse lockout relay control circuit at the reverse lockout relay connector.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, command the reverse lockout relay drive ON and OFF several times.
Does the test lamp turn ON and OFF with each command?		 Go to Step 9  Go to Step 14 
9
  1. Turn OFF the ignition.
  2. Install a 10-amp fused jumper between the switch side feed circuit of the reverse lockout relay and the reverse lockout solenoid supply voltage circuit at the reverse lockout relay connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the shift lever into the REVERSE position.
Does the shift lever move into the REVERSE position?		 Go to Step 10  Go to Step 15 
10
  1. Leave the fused jumper installed.
  2. Connect a test lamp between the reverse lockout solenoid supply voltage circuit at the reverse lockout solenoid connector and a good ground.
Does the test lamp illuminate?		 Go to Step 11  Go to Step 20 
11
  1. Turn OFF the ignition.
  2. Disconnect the reverse lockout solenoid.
  3. Leave the fused jumper installed.
  4. Connect a test lamp between the reverse lockout solenoid supply voltage circuit and the reverse lockout solenoid ground circuit at the reverse lockout solenoid connector.
  5. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?		 Go to Step 16  Go to Step 21 
12 Test for a short to battery positive voltage in the reverse lockout solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 16 
13 Test for a short to ground in the reverse lockout relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 17 
14 Test for an open in the reverse lockout relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 17 
15 Inspect for poor harness connections at the reverse lockout relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 22 
16 Inspect for poor harness connections at the reverse lockout solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 23 
17 Inspect for poor harness connections at the dash integration module (DIM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 25  Go to Step 24 
18 Repair the open in the reverse lockout relay coil side feed circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 25  -
19 Repair the open in the reverse lockout relay switch side feed circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 25  -
20 Repair the open in the reverse lockout solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 25  -
21 Repair the open in the reverse lockout solenoid ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 25  -
22 Replace the reverse lockout relay. Refer to Wiring Repairs in Wiring Systems.
Did you complete the replacement?		 Go to Step 25  -
23 Replace the reverse lockout solenoid. Refer to Shift Control Replacement in Automatic Transaxle - 4T80-E.
Did you complete the replacement?		 Go to Step 25  -
24 Replace the dash integration module (DIM). Refer to Dash Integration Module Replacement in Body Control System.
Did you complete the replacement?		 Go to Step 25  -
25 Operate the vehicle within the Conditions for Running the symptom.
Did you find and correct the condition?		 System OK Go to Step 2 
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