P0723:
P0723 code definition
The P0723 fault code is representative of the condition known as Output Speed Sensor Intermittent. Similar related codes include P0720, P0721, and P0722, which may all indicate a problem with the OSS (output speed sensor) or ISS (input speed sensor).
What the P0723 code means
P0723 is the OBD-II code which indicates an intermittent, erratic, or otherwise abnormal signal produced by the transmission’s output speed sensor (OSS). This sensor sends information to the PCM (powertrain control module), or in some vehicles, to a dedicated TCM (transmission control module) regarding rotational speed of the output shaft. Proper OSS function is crucial because if the signal is faulty, the transmission cannot shift appropriately. While each OSS design varies, in most cases the PCM detects erratic behavior by measuring how long the signal remains at a certain level of RPMs. If this level is maintained at too high of a level for too long, or changes in a way other than expected, the P0723 code will be triggered.
What causes the P0723 code?
Common causes of this fault code include:
A faulty output speed sensor
- A faulty input speed sensor
- Shorted or otherwise damaged wiring or connectors
- A faulty shift solenoid
- A faulty engine temperature sensor
- A damaged valve body
- Contaminated or dirty transmission fluid
- What are the symptoms of the P0723 code?
- The Check Engine light typically comes on, and there may be perceptible symptoms such as rough or absent shifting, decreased fuel efficiency, speedometer inaccuracy, stalls or hesitation, and/or engine misfires.
- How does a mechanic diagnose the P0723 code?
- As with most repairs, the diagnostic process begins with pulling stored codes and freeze frame data using a specialized scanner. If there are other codes present, these should be addressed in the order they occurred. The codes will then be cleared and the vehicle test driven to see if the code returns.
- A technician will visually inspect the wiring and involved components, as well as check the transmission fluid for debris. They will then use a voltmeter to measure the reference voltage and ground signal at the OSS. If one of these circuits is open, the mechanic will then check for continuity and resistance in the circuits.
If everything else is determined to be functioning correctly, your mechanic may use an oscilloscope to live monitor the transmission output speed sensor data. Most often, the output
speed sensor itself needs replacing, or there is a bad connection in the circuit.
Common mistakes when diagnosing the P0723 code
Due to the complexity of the transmission system, it’s easy to misdiagnose the OSS problem as a transmission or engine malfunction. The VSS (vehicle speed sensor) is also frequently mistakenly replaced in this situation.
How serious is the P0723 code?
This fault code can cause significant drivability problems, which may lead to further damage to the vehicle. It’s crucial to avoid driving as much as you can until you can have the repair made.
What repairs can fix the P0723 code?
Repairing the P0723 code may include the following steps:
Additional comments for consideration regarding the P0723 code
There are a number of things to take into consideration when faced with a speed sensor malfunction. The OSS doubles as the VSS (vehicle speed sensor) in some vehicles, so you want to be sure whether you have one or both before attempting repairs. In addition, some vehicles are equipped with a TFT (transmission fluid temperature) sensor, and if this sensor experiences a fault, it can trip an OSS fault code. Due to the wide variety of issues that can cause a P0723, you’re best off consulting a professional mechanic to help with the diagnosis and repair.
P0700:
P0700 code definition
P0700 is a generic OBD-II code that is indicating a fault within the transmission control system. This code may be seen with shift solenoid codes or other transmission codes.
What the P0700 code means
P0700 is set when the PCM detects a malfunction in the transmission control system. This malfunction causes the vehicle to set a Check Engine Light and trigger a failsafe mode. Once the failsafe mode is set it will remain until the fault is repaired or normal operation is detected.
What causes the P0700 code?
- Faulty transmission control module
- Transmission valve body fault
- Shift solenoid issues
- Open or short in the wiring harness
What are the symptoms of the P0700 code?
- Check Engine Light displayed on the dashboard
- Poor gas mileage
- Transmission shifting problems
- Engine stalling, running poorly, or dying
How does a mechanic diagnose the P0700 code?
- A mechanic will begin by hooking up a scan tool to the vehicle and checking for all codes present. If P0700 is found, it is generally not alone.
- Check all the freeze frame data for all codes to see under what circumstances the Check Engine Light was set.
- Next, the technician will clear the code and take the vehicle for a road test to duplicate the concern.
- Once this is performed, a visual inspection will be performed of the transmission and all wiring harnesses of the transmission.
- Lastly, the scan tool will be used to monitor transmission information while driving, such as solenoid operation and the condition of the valve body.
Common mistakes when diagnosing the P0700 code
Mistakes are made when all steps are not followed or are not completed at all. Though a car may have a typical repair that fixes the P0700 code, this may not be true in all circumstances, which is why diagnosis is performed step-by-step.
How serious is the P0700 code?
P0700 can potentially indicate larger issues with the transmission or the future of the transmission. Some serious drivability problems can come along with this code and care should be taken.
The vehicle should not be driven if it is having trouble changing gears or it is stuck in one gear as this will cause further damage and is a safety hazard on the road.
What repairs can fix the P0700 code?
Additional comments for consideration regarding the P0700 code
P0700 is commonly seen with one or more shift solenoid codes. This may be as simple as low fluid due to a transmission leak, or a failure of the transmission on the extreme side of the spectrum.
When a transmission is failing, it is not uncommon to see metal flakes in in the fluid. These flakes clog shift solenoids and the valve bodies and can result in the P0700 code. When excessive metal buildup is found in the transmission, it is due to mechanical wear and can be an indication the transmission needs rebuilt or replaced.
. Going to try to find how many miles i put on it since...this is ridiculous. This why I didnt even think of mount....
