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Error Code P0895 is defined as Shift Time Too Short. This is a generic trouble code, meaning it applies to all vehicles with the OBD-II system, especially those made since 1996 up to the present. This includes vehicles from, but not limited to BMW, Citroen, Dodge, Ford, Peugeot, Land Rover, Mercedes Benz, etc. Specifications on the definition, diagnostics, and repairs may vary from one make, year, model, and power configuration to another.
If the vehicle stores Error Code P0895, the PCM (powertrain control module) received a data input signal from the input and output speed sensors that indicate that the interval to shift between gears is insufficient.
The Transmission Control Module (TCM) may be a stand-alone unit, but in most cases, it is integrated into a single housing in the Engine Control Module (ECM), which is referred to as the PCM.
To calculate automatic transmission shift energy, the PCM uses multiple input signals from multiple engine transmission sensors. A high-pressure pump (inside the transmission) forces fluid through the valve body to the sprag assembly, apart from lubricating and cooling transmissions. The high-pressure fluid allows clutches to momentarily separate from the sprag to change the gear ratio smoothly.
To help regulate the fluid pressure, one or more electronic pressure control (EPC) solenoid is installed. This sensor provides the PCM the pertinent data regarding the fluid pressure at different points in the transmission. Electronic shift solenoids are then used to interrupt the high-pressure flow, allowing the transmission to shift the gears when commanded. To determine whether the transmission is shifting efficiently, the PCM uses voltage input signals from the transmission input speed sensor and transmission output speed sensor.
If the PCM determines the engagement of multiple gears in the automatic transmission, it stores the error code and activates the Check Engine Light.
This may be caused by electrical or mechanical failure.
- Insufficient transmission fluid pressure
- Transmission slips
- Delayed transmission
- Harsh gear engagement
- Erratic shift patterns
- Strong burnt odor in the transmission fluid
- Unusual whining noise from the transmission
- Faulty high-pressure pump in the transmission
- Disastrous internal (mechanical) transmission failure
- Faulty shift solenoids
- Shorted wiring in the EPC solenoid or EP sensors
- Damaged EPC solenoid or EP sensors
- Defective PCM or programming error in PCM
How to Check
Start by making sure the transmission fluid is clean and at the appropriate level.
If transmission fluid is low, then there must be a leak. Find the source of the leak and repair it. Refill the transmission fluid at the recommended level.
If the transmission fluid looks dark and smells burnt, then it must be replaced. To replace the transmission fluid, remove the transmission pan (along with the draining torque converter) or flush the transmission (the latter is the recommended step). Whichever you choose, you need to replace the filter as well.
When removing the pan from the transmission, try to preserve the debris that landed on the pan. If the pan looks clear of debris, then you can assume that the vehicle’s clutches are intact. An excessive amount of debris means too much friction (and stuck to the magnet), which means a qualified technician must rebuild the transmission.
With the transmission fluid at the right level, proceed with the diagnostics using a DVOM (digital volt/ohmmeter), as well as diagnostic information for the specific vehicle. Locate the TSB (technical service bulletin) that matches the error code, vehicle, year, model, engine size, as well as symptoms.
Test the transmission fluid pressure at the appropriate opening on the transmission using the manual pressure gauge. If the pressure is not within the specifications, you may need to rebuild or replace the pump. This may also require a transmission rebuild, which a qualified technician can only do.
If the fluid is within the specifications, proceed to the second step.
Next, retrieve all stored data and pertinent freeze frame data by connecting the scanner to the vehicle’s diagnostic connector. It’s best to write this information down before clearing the codes and taking the vehicle for a test drive.
Test-drive the vehicle until it enters readiness mode or resets.
If the PCM enters readiness mode, that means the problem is still intermittent and difficult to diagnose. You may need to wait for the condition to develop before you can accurately diagnose it.
If the code resets immediately, then search for the vehicle information source for proper diagnostics. Look for the flow-chart, testing procedures and specifications of the components, connector face views, and pin-out charts.
Test the voltage and ground circuits at the EPC solenoids and EP sensors using the DVOM. If there are voltage and ground, then test the EPC solenoid EP sensors. You can consider any components that we’re unable to comply with the specifications defective. If they are functional, then test the signal circuit that is input to the PCM.
If both the EPC solenoids and EP sensors are functional and present, use the DVOM to test the system circuits.
The voltage drop testing method works well for this task. Disconnect all controllers from the circuit before testing resistance with the DVOM.
High-mileage vehicles may experience transmission high-pressure pump failure
A low fluid condition may cause transmission shift time codes
How to Fix
- Refill or replacement of transmission fluid
- Fixing leaks in the transmission fluid
- Replacement of transmission solenoid
- Rebuilding of transmission and torque converter
This code means serious shifting problems have been detected. This must be addressed as soon as possible.
Vehicles with high mileage are likely to experience failure in the high-pressure transmission pump.
Low fluid condition can also cause transmission shift time error codes.