Noticed that the tranny seems to slip but it may just be that it is not shifting into higher gears. High RPM's but low ground speed.
Also noticed that Overdrive light is blinking.
Seems to run fine with cold engine/ tranny, but gets worse as it warms up.
The flashing O/D light usually means you have a bad speed sensor that sends speed info to the engine & trans computer.
Vehicle Speed Sensor
The vehicle speed sensor (VSS) (Figure 42) is a variable reluctance or Hall-effect sensor that generates a waveform with a frequency that is proportional to the speed of the vehicle. If the vehicle is moving at a relatively low velocity, the sensor produces a signal with a low frequency. As the vehicle velocity increases, the sensor generates a signal with a higher frequency. The PCM uses the frequency signal generated by the VSS (and other inputs) to control such parameters as fuel injection, ignition control, transmission/transaxle shift scheduling and torque converter clutch scheduling.
-------------------------------------------------------------------
Vehicle Speed Sensor
The vehicle speed sensor (VSS) (Figure 42) is a variable reluctance or Hall-effect sensor that generates a waveform with a frequency that is proportional to the speed of the vehicle. If the vehicle is moving at a relatively low velocity, the sensor produces a signal with a low frequency. As the vehicle velocity increases, the sensor generates a signal with a higher frequency. The PCM uses the frequency signal generated by the VSS (and other inputs) to control such parameters as fuel injection, ignition control, transmission/transaxle shift scheduling and torque converter clutch scheduling.
-------------------------------------------
Some trans use an OSS, Output Shaft Sensor instead of a VSS. Depends on which trans you have, 4R100 or 4R70W
Transmission Control Switch (TCS) and Transmission Control Indicator Lamp (TCIL)
The transmission control switch (TCS) is a momentary contact switch. When the switch is pressed, a signal is sent to the powertrain control module (PCM) to allow automatic shifts from first through fourth gears or first through third gears only. The PCM energizes the transmission control indicator lamp (TCIL) when the switch is off.
The TCIL indicates overdrive cancel mode activated (lamp on) and electronic pressure control (EPC) circuit shorted (lamp flashing) or monitored sensor failure.
Output Shaft Speed (OSS) Sensor
The output shaft speed (OSS) sensor is a magnetic pickup, located at the output shaft ring gear, that sends a signal to the powertrain control module (PCM) to indicate transmission output shaft speed. The OSS is used for torque converter clutch control, shift scheduling and to determine electronic pressure control.
Need solution for above problem
My TCIL flashes, checked with code reader. got P1747, pres ctrl sol. A circuit shoted. no visable short on external wiring. fluid in conector on case. could that be the short? or should i look in side?
SOURCE: hard shift and blinking overdrive
The blinking overdrive button is telling u that a serious fault has occurred in the electronic controls or a mechanical fault such as excess slippage is occurring.
SOURCE: 1998 ford expedition blinking overdrive light
This blinking light indicates a problem. You will have to have it scanned for trouble codes to find out
what it is.
The
shifter needs to be inspected. The shifter assembly is got misaligned, it has
to be open and realign.
There
are many other possibilities. But if it was working right up till now and
suddenly this occurred then its shifter
assembly alignment issue.
Also
i suggest you to refer these gear shift issues, which are mostly noticed. These
are direct links with appropriate solutions to
the specific problems of gear ****.
GEAR SHIFT ISSUES
http://howtobyme.blogspot.com/2011/11/chrysler-pt-cruiser-only-goes-in-first.html
----------
Car is stuck in park and the shift will not move?
http://howtobyme.blogspot.com/2011/08/car-is-stuck-in-park-and-shift-will-not.html
http://howtobyme.blogspot.com/2011/11/car-will-not-come-out-of-park.html
http://howtobyme.blogspot.com/2011/11/automatic-transmission-will-not-go-into.html
----------
http://schematicsdiagram.blogspot.com/2011/12/car-wont-downshift-sometimes.html
http://schematicsdiagram.blogspot.com/2011/12/buick-park-avenuetransmission-will.html
http://schematicsdiagram.blogspot.com/2011/12/car-transmission-will-no-go-into-park.html
http://schematicsdiagram.blogspot.com/2011/12/shift-indicator-directly-goes-to-2nd.html
http://schematicsdiagram.blogspot.com/2012/01/third-gear-missing-and-engine-losing.html
http://technoanswers.blogspot.com/2012/01/chevrolet-silverado-has-whining-sound.html
http://technoanswers.blogspot.com/2012/01/hard-to-shift-gears-on-manual.html
http://technoanswers.blogspot.com/2012/01/car-hard-shift-at-slow-speeds.html
http://technoanswers.blogspot.com/2012/01/automatic-transmission-shift-lever-hard.html
http://schematicsdiagram.blogspot.in/2012/02/2000-nissan-maxima-shifts-hard.html
-------
http://schematicsdiagram.blogspot.in/2012/03/vehicle-noticed-sluggish-delayed-shifts.html
-------
http://schematicsdiagram.blogspot.in/2012/06/2007-hyundai-santa-fe-will-not-shift.html
These details will help.
Thanks.
4,668 views
Usually answered in minutes!
I have a very similar issue, 'cept mine seems to do better warm. It always seems to be slippery before it is warmed up and in town, on the highway I rarely have problems. OD light blinking also. Mine is a 1998.
It's usually shifting between 2 and 3 and hasnt gotten any worse (or better) in 10,000 miles. Seems to almost be skipping 3 and revving up high then right into OD.
×