Here is a description of the 4 possible codes that can flash from jumping pins 5 & 13 of obd2 port (5 is a ground pin, 13 is the transfer case pin). Mine showed code 2. It can also flash multiple codes. There will be a 3 sec pause between codes, then once all codes are flased they will flash again over and over.
1- Ram Standby power fault: Possible open connection or short in the TCCM fuse circuit. However, this code is often considered normal and may be caused by clearing the codes.
2 - Encoder fault: Every time the t-case position moves, the TCCM checks the encoder’s readings during the shift. If something isn't right, it will increment an error counter by 4. A successful reading decreases the counter by 1. If the counter reaches 32, the TCCM determines the encoder faulty, and bypasses 4hi. Check for loose wires and excessive dirt/moisture near all connectors.
3 – TCCM (Transfer Case Control Module) motor circuit: Basically, every time the TCCM is powered up, it tests the encoder motor. If something isn't right, it will trip the code 3.
Possible causes
1. Open or shorted circuit between encoder motor and TCCM.
2. Short/open connection in the motor itself
3. Malfunctioning motor relay
(this can cause the indicator lights to flash all the time (normal driving). If this happens, it must be fixed IMEDIATELY. It can cause encoder motor failure even when the ignition is off.
4 - Ram/Rom failure: Internal software failure. Pull the TCCM fuse for 3 mins. Then replace it, and cycle the ignition from off to run 5 times. Then re-check the codes. If code 4 still is present, then the TCCM must be replaced.