A P1730 OBDII code means that the TCM is not receiving the proper voltage signal from the various sensors and switches. The TCM uses this data to compare the gear position and operating conditions for each of the pressure switches when a particular gear is engaged.
How Serious is the Code?
The P1730 Nissan diagnostic trouble code can be fairly serious, and can result in a number of drivability issues including harsh shifting and limp mode (where the vehicle is locked into 2nd gear).
Symptoms of a P1730 include:
- Harsh shifting
- Limp Mode
- Damaged wiring or connectors
- Solenoid wiring problem
- Failed low coast brake solenoid valve
- Failed ATF pressure switch 2
How to Diagnose the Code?
When trying to diagnose a P1730 Nissan OBD2 code, the first step should be to analyze the wiring and connectors along the transmission wiring harness going to the TCM. If no problems are found, then the low coast brake solenoid valve and ATF pressure switches should be suspected.
What Repairs Will Fix P1730?
- Repair damaged wiring and/or connectors
- Replace low coast brake solenoid valve
- Replace ATF pressure switch 2