P259C BMW Fault Code
Check P259C OBD Fault Code ReasonThe issue covered by the bulletin involves a power steering noise/whine or fluid leak from the power steering pump, gear or high pressure side power steering hose during extreme low outdoor temperature operation.
P259C Code Symptoms :
If your vehicle failed a P259C test and the P259C Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses P259C a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look : Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression.
Diagnosis And Repairing P259C
Parts or components should not be replaced with reference to only a P259C DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.
How to fix P259C code ?
- Continuous oil flow to the VCT piston chamber
- Damaged VCT phaser
- Incorrect Positive Crankcase Ventilation (PCV) hose connection
- Oil flow restriction in the oil passages or the VCT valve body
On some transmissions, such as automated manual transmissions or automatic transmissions with manual mode, the GSP switch lets the TCM know whether or not the driver has selected automatic or manual function.
On manual transmissions, the GSP switch informs the TCM which gear the driver is selecting, and may function as a neutral safety switch, depending on system design. The TCM also uses the gate select position switch to monitor transmission operation. For example, if the driver selects manual mode and selects 3rd gear on an automatic transmission, the TCM may monitor speed sensors to detect clutch and brake slippage.
