P1684

P1684 - Battery Was Disconnected






For a complete wiring diagram, refer to.

Theory of Operation

Note: This is not a fault code. It exists to provide reference information only. A battery backed RAM is used to maintain some learned values. When the battery is disconnected, this memory is lost. When the battery is reconnected, the loss of learned values will be detected by the controller. The code will be set and the learned values will be initialized to known constants and the learning process will continue. Setting the code has no effect except for re-initialization of learned values.

• When Monitored: After a reset (ignition turned to the RUN position).

• Set Condition: The checksum of the battery backed RAM does not match the stored checksum. Set time: less than 7 ms.






Always perform the pre-diagnostic troubleshooting procedure before proceeding. Refer to => Non-DTC Based Diagnostics. Pre-Diagnostic Troubleshooting Procedure

Test Step 1 - Battery was Disconnected

Has the battery been disconnected, lost it's charge, or been replaced recently?

Yes

• Disconnecting or replacing the battery will set this DTC. Erase the DTC.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

No

• Go to Test Step 2.

Test Step 2 - Was Quick Learn Performed

Has a quick learn procedure been performed?

Yes

• Performing quick learn will set this DTC. Erase the DTC.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

No

• Go to Test Step 3.

Test Step 3 - PCM Replaced or Disconnected

Has the PCM been replaced or disconnected?

Yes

• Replacing or disconnecting the PCM will set this DTC. Erase the DTC.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

No

• Go to Test Step 4.

Test Step 4 - Check the Fused B(+) Circuit







Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special tool #8815 to perform diagnosis.

• Turn the ignition OFF to the lock position.

• Disconnect the PCM C1 harness connector.

• Check connectors - Clean/repair as necessary.

• Using a 12 volt test light connected to ground, check the fused B(+) circuit.

• The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

• Go to Test Step 5.

No

• Repair the fused B(+) circuit for an open. If the fuse is open make sure to check for a short to ground.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

Test Step 5 - Ground Circuits






• Turn the ignition OFF to the lock position.

• Disconnect the PCM C4 harness connector and connect Miller tool #8815.

• Using a 12 volt test light connected to 12 volts, check the ground circuits in the appropriate terminals of Miller tool #8815.

• The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly for all of the ground circuits?

Yes

• Go to Test Step 6.

No

• Repair the ground circuits for an open.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

Test Step 6 - Intermittent Wiring and Connectors

• The conditions necessary to set the DTC are not present at this time.

• Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.

• Wiggle the wires while checking for shorted and open circuits.

• With the scan tool, check the DTC event data to help identify the conditions in which the DTC was set.

Were there any problems found?

Yes

• Repair as necessary.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

No

• Test Complete.