DTC P1101 (N_SW): Neutral Position Switch Circuit Malfunction (M/T)

Turn ignition on. Using DVOM connected to chassis ground, backprobe ECM connector terminal No. 82. See appropriate wiring diagram in WIRING DIAGRAMS article. Place transmission in Neutral. If voltage reading is 4.5-5.5 volts, go to next step. If voltage reading is not 4.5-5.5 volts, go to step 3).
With DVOM still connected to ECM connector terminal No. 82, move transmission shifter to another gear. If voltage reading is more than one volt, go to next step. If voltage reading is one volt or less, check for poor terminal contact in ECM connector. If terminal contacts are okay, replace ECM with a known good unit and retest.
Turn ignition off. Disconnect neutral position switch connector. Check resistance between neutral position switch terminal No. 1 and No. 2. If resistance is more than one megohm in neutral position and less than one ohm in all other positions, go to next step. If resistance is not within specifications, replace neutral position switch.
Disconnect ECM connector. Check resistance between ECM connector terminal No. 82 and neutral position switch connector terminal No. 1. If resistance is one ohm or less, go to next step. If resistance is more than one ohm, repair open in wiring between ECM and neutral position switch connectors.
Check resistance between ECM connector terminal No. 82 and chassis ground. If resistance is 10 ohms or less, check for short to ground in wiring between ECM and neutral position switch connectors. If resistance is more than 10 ohms, go to next step.
Check resistance between neutral position switch connector terminal No. 2 and chassis ground. If resistance is 5 ohms or less, check for poor contact in switch connector. If connector is okay, replace ECM. If resistance is more than 5 ohms, check for open in wiring between neutral position switch and engine ground terminal.