P0700 Fault Code

Long Description

Fault code P0700 is logged when the powertrain control module (PCM) has detected an issue within the transmission control system (TCM). This code can represent various malfunctions within the TCM.

A TCM is typically used exclusively in a vehicle with an automatic transmission. Its role is to monitor the various sensors and actuators needed for the proper operation of the automatic transmission.

The TCM then sends valuable data to the engine control unit (ECU) to allow for optimal performance. Without the correct communication between the two control units, the vehicle will be unable to perform properly. This can even lead to gear shifting being impossible.

The PCM is simply the combination of the transmission and engine control units working together.

Only vehicles with an automatic transmission will be able to log a P0700 code. Some of the most commonly reported P0700 codes come from manufacturers like BMW, Jeep, Kia, and Subaru.

Other Signs of This Problem

There can typically be several noticeable symptoms of a code like P0700. These can be used to inform the driver of a potentially very serious issue.

The first and most obvious sign will be that the Check Engine light will be illuminated. Additionally, the vehicle will also enter limp mode or fail-safe mode depending on the manufacturer.

Another noticeable sign is that the vehicle will have trouble shifting gears as a direct result of the malfunction.

Fuel economy will also be greatly reduced as the incorrect gear will be used, resulting in excessive power output from the engine.

Other transmission codes could be logged as well. These can be codes like P0701 and P0705 up to P0714.

What Could Be The Problem?

There are several things that can cause P0700 to be logged. These can relate to various moving parts, as well as faulty electronics in the circuitry.

A faulty transmission valve body can cause this issue by sending incorrect output signals to the TCM.

Damaged or faulty shift solenoids can also be the cause of the issue. This can come with delayed or unpredictable shifting from the gearbox. This can also cause the transmission to skip gears.

A fault TCM is another potential cause. This can also be a result of outdated software.

Issues like poor wiring can also lead to the code being logged. Short or open circuits also have this potential.

Fixes

There are various fixes that can be done to solve fault code P0700. These changed depending on which system is at fault.

If the TCM is faulty in any way, it should be replaced.

Any faulty parts should also be fixed or replaced accordingly. If the valve body is damaged or otherwise malfunctioning, it should be replaced.

The shift solenoids should be tested and changed if they are not in working order.

Any wiring should be checked for damage or fraying. These must be fixed if present. Additionally, the connections should be checked that they are clean and properly fixed.

Seriousness

Fault code P0700 should be considered a very serious problem. Stop driving immediately if you notice any of the signs.

Additionally, the fail-safe or limp mode will prevent the proper operation of the vehicle. This means the issue should be fixed immediately to prevent further damage and allow for normal operation.