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For 1990-2009 cars only
Table 1: Transmission Range Switch Valid Input Combinations
Table 2: DTC P0705, P0706-Transaxle Range Switch Circuit

Object Number: 337307  Size: MF
Engine Controls Component Views
Cell 21: Instrument Cluster, Automatic Transmission
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The transmission on this vehicle has a Park Neutral Position (PNP) and Back-up switch. This switch incorporates a transmission range selector switch. There are four inputs (PRND A, B, C, P) which are switches to ground. The four switches have an unique switch pattern. The PCM uses the combination of the switch patterns in order to determine the gear selected by the driver.

This diagnostic monitors the four inputs in order to determine what gear position the transmission is in. When the PCM detects that an illegal range has occurred, this DTC sets.

Conditions for Running the DTC

Ignition voltage is greater than 8.0 volts.

Conditions for Setting the DTC

    • The transmission Range (select lever) switch indicates an illegal position.
    • The PCM detects an illegal range for 10.0 seconds.

Action Taken When the DTC Sets

    • The powertrain control module (PCM) stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

Conditions for Clearing the DTC

    • A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
    • Use a scan tool in order to clear the DTC.

Diagnostic Aids

Important: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.

The following may cause an intermittent:

    • Inspect for poor connections. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
    • Corrosion
    • Mis-routed harness
    • Rubbed through wire insulation
    • Broken wire inside the insulation
    • Manipulate related wiring and connectors while observing the PRND Range parameters (PRND A, B, C, P) on the scan tool. If the manipulation causes an intermittent, the corresponding parameter changes on the scan tool.
    • Using Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can aid in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also aid determining how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.
         For an intermittent, refer to Symptoms .

The table below is the normal state that each gear range should indicate. ON indicates the circuit is low (switched/shorted to a ground). OFF indicates the circuit is high (open). Another parameter to display is PRND Range. This parameter displays the current gear range the transmission is in. When there is an invalid gear range, the parameter indicates Invalid.

Transmission Range Switch Valid Input Combinations

Gear Selector Position

Scan Tool Trans Range ABCP Display

A

B

C

P

Park (P)

ON

OFF

OFF

ON

Reverse (R)

ON

ON

OFF

OFF

Neutral (N)

OFF

ON

OFF

ON

Drive4 (OD)

OFF

ON

ON

OFF

Drive3 (3)

ON

ON

ON

ON

Drive2 (2)

ON

OFF

ON

OFF

Drive 1 (1)

OFF

OFF

ON

ON

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This verifies whether a malfunction is present. If the PCM does not detect any invalid ranges, this indicates the fault is not present. You may have repaired the fault when the switch was adjusted.

  2. Any circuit that you suspect is causing an intermittent condition, thoroughly inspect for the following:

  3. • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal to wiring connections
    • Physical damage to the wiring harness
  4. A circuit malfunction causes the Trans Range to display an invalid range on the scan tool. Jumping each circuit to ground simulates the trans range switch operation and tests the circuitry and PCM. While the transmission range switch is disconnected and the circuits are not grounded, the scan tool should indicate OFF. A value that indicates ON with no jumper to ground indicates a grounded circuit or malfunctioning PCM.

  5. If you have not found any malfunctions at this point and no additional DTCs were set, refer to Diagnostic Aids for additional information.

DTC P0705, P0706-Transaxle Range Switch Circuit

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important: Adjust the PNP switch and the shift cable/lever before proceeding with this diagnostic table. Refer to Park/Neutral Position Switch Adjustment (4L60E) or Park/Neutral Position Switch Adjustment (4L80E) in Transmission.

  1. Turn ON the ignition leaving the engine OFF.
  2. Install a scan tool.
  3. Move the gear selector through all the gear ranges while monitoring the PRND A, B, C, P and the Trans PRND parameter on the scan tool.

Does the scan tool indicate an invalid position in any of the gear ranges?

--

Go to Step 3

Go to Diagnostic Aids

3

Compare the scan tool values with the Transmission Range Switch Valid Input Combinations table.

Does the scan tool display all the circuits as OFF?

--

Go to Step 4

Go to Step 5

4

  1. Test the PNP switch ground circuit for an open or poor connection.
  2. If you find a condition, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 5

5

  1. Move the gear selector through all of the gear ranges and observe which circuits do not correspond with the Transmission Range Switch Valid Input Combinations table.
  2. Disconnect the trans range switch electrical connector.
  3. Jumper the circuit with the incorrect value to ground.

Does the scan tool change from OFF to ON when the circuit was jumped to ground?

--

Go to Step 8

Go to Step 6

6

Test the affected circuit for an open or a short to ground and repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 7

7

  1. Test for a poor connection at the PCM connector and repair as necessary. Refer to Wiring Repairs in Wiring Systems.
  2. If you find a poor connection repair the condition as necessary. Refer to Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

8

  1. Inspect for a poor connection at the PNP/Back Up Switch electrical connector. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
  2. If you find a poor connection repair the condition as necessary. Refer to Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

9

Replace the PNP/Back Up Switch. Refer to Park/Neutral Position Switch Replacement (4L60E) or Park/Neutral Position Switch Replacement (4L80E) in Transmission.

Is the action complete?

--

Go to Step 11

--

10

Important:: Program the replacement PCM. Refer to Powertrain Control Module Replacement/Programming .

Replace the PCM.

Is the action complete?

--

Go to Step 11

--

11

  1. Select the Diagnostic Trouble Code (DTC) option and the Clear DTC option using the scan tool.
  2. Idle the engine at the normal operating temperature.
  3. Operate the vehicle within the Conditions for Running this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic has ran and passed?

--

Go to Step 12

Go to Step 2

12

Verify if any DTCs are set.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to applicable DTC table

System OK