What P1816 means: Transmission Fluid Pressure (TFP) Manual Valve Position Switch — Park/Neutral with drive ratio. It is a transmission code.
Does LockNCal handle this? No — transmission faults aren’t part of our mobile safety-systems service, so this one is best diagnosed by a qualified repair shop. If the same scan also shows airbag/SRS, ADAS, or key & immobilizer codes, those we do handle — call or text (469) 277-7277.
Because P1816 is a transmission fault, the symptoms and the correct repair depend on that system. Have the code confirmed with a diagnostic scan and repaired by a qualified technician before it causes further problems.
