OBD 1605

Nissan Altima OBD code 1605

P1605 NISSAN - Automatic Transmission Communication

The 1605 code for your year Altima is either due to a weak battery or a bad AT control unit.
Weak battery
- Faulty Transmission Control Module (TCM)
- Harness is open or shorted between TCM and Engine Control Module (ECM)
- Poor circuit electrical connection between TCM and ECM

Here is the steps to check the system out yourself.


https://dl.dropboxusercontent.com/u/105565483/1d.pdf

If the transmission seems to function fine,then it is more likely to be either a weak battery or an opened or shorted communication line between the ECM and the A/T control unit?
Malfunction is detected when an incorrect signal from Transmission control module (TCM) is sent to Engine Control Module (ECM).


I would start by clearing the code and see if it returns. If it does, I would check the battery and the charging system voltage before replacing a control unit or getting crazy about checking wiring.

This will help.
Thanks.

Where is the transmission code located on the car?

2004 Volkswagen New Beetle 

Where is the transmission code located on the car?

The code letters on an automatic transaxle are on a metal plate near where the transaxle butts up against the engine. The stamped transaxle type is in the metal of the housing, away from the engine and closer to the front wheel. Both the code letters and tight become visible by your raising the vehicle up onto jack stands and viewing from underneath.