P0790 – Transmission mode selection switch -circuit malfunction
Last Updated 2016-01-17
Ed.D, PhD Philosophy, BSME
|Code||Fault Location||Probable Cause|
|P0790|| Transmission mode selection switch -circuit malfunction |
(Buy Part On Amazon)
|Wiring, transmission mode selection switch, ECM/PCM!TCM|
We recommend Torque Pro
Table of Contents
- What Does Code P0790 Mean?
- What are the common causes of code P0790 ?
- What are the symptoms of code P0790 ?
- Codes Related to P0790
- Get Help with P0790
What Does Code P0790 Mean?
DTC P0790 sets when the PCM/TCM has detected a malfunction in the electrical circuit of the transmission mode selector. The switch, system wiring and connectors, and mode actuator are all included in this circuit.
The transmission range (TR) switch or mode selector, also called the manual lever position (MLP) sensor, is used as an input to the PCM/TCM, which indicates the drive range requested by the driver. The transmission range switch is usually located on the outside of the case on the transmission/transaxle housing and attached to the shifter. As the gear range selector is moved, TR switch can make a variety of switch connections for each gear range. These inputs allow the TCM to determine which gear range has been selected. The switch is used by the TCM to
- Keep the engine from starting in any gear position except park or neutral
- Allow a progressive 1–2–3–4 shift sequence in drive
- Limit upshifts in manual ranges
- Operate the backup lights in reverse
NOTE: Whenever diagnosing a 700 series DTC (Diagnostic Trouble Code) with a transmission, transfer case or other driveline components, check for a DTC under chassis and body systems, not just under “P” or powertrain/engine or emission control type codes. Module communications DTCs are “U” codes. These are most often found when looking for DTCs under chassis or body systems. Chassis related codes are labeled “C” and body system related codes are labeled “B” codes and these can cause drivetrain issues if they affect a sensor that is also used by the heating and air conditioning system.
What are the common causes of code P0790 ?
- Water contamination of the transmission mode switch
- Open or shorted electrical wiring, damaged, corroded, or disconnected wiring or connectors
What are the symptoms of code P0790 ?
- MIL (Malfunction Indicator Lamp [Check Engine & Service Engine Soon])lights on with stored historical P0790
- There may be no distinguishable symptoms
- Torque converter clutch will not function
- In some applications, the overdrive light may flash
- TCM/PCM may also enter “limp-in” mode when this code is stored with harsh shifts
Codes Related to P0790
Help Us Help You
Please comment below describing your issue as well as the specifics of your vehicle (make, model, year, miles, and engine), and one of our mechanics will respond as soon as possible. We appreciate a $9.99 donation via the payment button below.
Buenos dias,me sale.el fallo 790,algo relacionado con,la temperatura del coche,la aguja de la temperatura veces me sube como un,balanseo hacia arriba se enciende la luz roja de stop pero todo esto es un,balanceo rapido subiendo,y,vajando al,instnte.,,¿Cual seria su areglo o como lo hacia?gracias.