Circuit Description

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.

Transmission range sensor is also referred to as park/neutral position switch. The park/neutral position switch detects the shift lever position and sends signals to the ECM. The ECM receives signals (P, R, N, D, 4, 3, 2 and L) from the park/neutral position switch. When the signal is not sent to the ECM from the park/neutral position switch, the ECM judges that the shift lever is in "D" position. When the shift lever is in the 4 position (with transmission control switch for "D" and "4" pressed), "4" in the shift position indicator light will come on and when the shift lever is in the "D" position (with transmission control switch for "D" and "4" released), "D" in the shift position indicator light will come on. When the shift lever is in the "L" position (with transmission control switch for "2v and "L" pressed), "L" in the shift position indicator light will come on and when the shift lever is in the "2" position (with transmission control switch for "2" and "L" released), "2" in the shift position indicator light will come on. DTC is set when all switches are OFF simultaneously for P, R, N, D, 3 and 2 positions, or when 2 or more switches are ON simultaneously for P, R, N, (D 4), 3 and (2 L) positions. Possible causes are:

Open or short in park/neutral position switch circuit.
Faulty park/neutral position switch.
Faulty ECM.