Overdrive not working?

[apple2005]

My grand marquis LS 1997 model overdrive button is not working. I checked in one workshop. They told me to check by auto electrician. The auto electrician told me that he will open the dashboard to see if the button is faulty? OR there may be problem in the gears? Selenoids?

May I ask the geeks, what will happen if it is not working? What is this overdrive for?
A detailed answer will be highly appreciated.

[87gtVIC]

The overdrive is meant to help improve gas mileage during highway driving. If it is not working you will just be burning more gas than you need by having the engine operate at a higher rpm. I am not familiar with where the overdrive button is positioned, but if it on the tip of your shifter, assuming it is a column shift, than my first guess would be through the everyday use of it the wires either pulled out or lost contact. If this is the case you may need a new shifter handle to solve the problem.

A similar problem occurred in my fathers Expedition not to long ago.

[apple2005]

Thank you so much for your reply.

[87gtVIC]

No problem, it could be other things as well, things that i do not know of. More help will come.

[Rizzo]

Not using Overdrive at 70+ mph is dangerous.

When you push the button the OD light does not come on ?

When you are driving 55 or so when you push the button do you feel a down shift ?

How does the car shift otherwise ?

[apple2005]

Not using Overdrive at 70+ mph is dangerous.

When you push the button the OD light does not come on ?

When you are driving 55 or so when you push the button do you feel a down shift ?

How does the car shift otherwise ?

Thanks AKA_rizzo for your concern.
Nothing happens when I push the button. No light on.
I am feeling the shift when I give gas.
I usually drive 100- 120 km/hour on highways. Sometimes 130km/hour when overtaking. I don't know in Miles. I am not familiar with miles.

I will appreciate further help.

[gadget73]

100-120 kph is 62-74 mph. You can run those speeds without overdrive, but it wastes fuel.

The button actually shuts overdrive off, the light comes on to indicate overdrive is off, not on. If you can feel it shift three times during normal acceleration, you're in overdrive. Its possible you might not be able to lock it into drive if the button isn't working.

[Rizzo]

Looks like we are all gettin at the bulb is burned out but the function is still there.

If you are traveling at 80 KPH and press the button, If you feel a downshift then you are ok.

Replacing the bulb is not easy but it's NOT complicated either. While you have the gauge cluster out consider replacing all the bulbs at once since you have it open already.

A link to a write-up is below.

http://www.crownvic.net/ubbthreads/ubbthreads.php?ubb=showflat&Number=1206416#Post1206416

Now please don't decide to not replace the bulb if this is the case. The OD light serves as a "Check engine" Light for the trans. You wanna know if its blinking.

[apple2005]

Thanks gadget73 for your support.
I don't remember now how many times it shifts during acceleration. It means that my overdrive is probably working but light is not coming on display, Right?
My Gas consumption is 15/100 average.

Further help will be highly appreciated.

[86VickyLX]

The light only comes on when the button is pressed. It's used to shut overdrive off. The only time I would recommend using that switch would be if you are towing something, or constantly going up and down hills, to protect your overdrive in your transmission. The switch is reset to the off position whenever the ignition is turned off. Just do what gadget said and see how many times it shifts. My bet is the bulb is blown. Unless you're towing something, or live in a hilly area, I wouldn't worry about it.




*Edit*
A very simple way to check if bulb is blown. Put the ignition in run mode, but do not start the car. If the light is not lit, then your bulb for the light is blown.

[apple2005]

The light only comes on when the button is pressed. It's used to shut overdrive off. The only time I would recommend using that switch would be if you are towing something, or constantly going up and down hills, to protect your overdrive in your transmission. The switch is reset to the off position whenever the ignition is turned off. Just do what gadget said and see how many times it shifts. My bet is the bulb is blown. Unless you're towing something, or live in a hilly area, I wouldn't worry about it.

*Edit*
A very simple way to check if bulb is blown. Put the ignition in run mode, but do not start the car. If the light is not lit, then your bulb for the light is blown.

Thanks 86vickyLX for your help.
I put the ignition into run mode, I saw only usual display + battery+ oil icons in red. No other indicator or light.

[86VickyLX]

Then most likely, the bulb is blown. Glad to help mang. You gonna replace the bulb?

[Spaz]

the o/d indicator is not supposed to light up in the run position with the car off

[drock96marquis]

the o/d indicator is not supposed to light up in the run position with the car off

No, the OD OFF lamp DOES illuminate briefly when the ignition is first turned from off to run (before starting) for the bulb proveout check

Thanks 86vickyLX for your help.
I put the ignition into run mode, I saw only usual display + battery+ oil icons in red. No other indicator or light.

Then you either have multiple bulbs out, or you aren't very observant :tongue:

The Airbag, seat belt, ABS (if equipped), Air Suspension (if equipped), Check Engine and the OD OFF lamps will ALL illuminate for a short period when you FIRST turn the ignition from off to run but not starting.


This is of course assuming you have an analog cluster. If you have the digital dash, the warnings on the cluster are VFD and rarely if ever go bad. There are also more warnings that will display during the prove-out period than an analog cluster (ie washer fluid, door / trunk ajar, etc.)



Try it again and see what lights up.

If the car is NOT down shifting to third from overdrive (depressing the button disables overdrive - illuminating the green OD OFF lamp, pressing it once again turns it back on) while cruising at free way speeds suspect the switch itself or switch wiring near base of shifter.

If the car is indeed downshifting when the button is depressed, WITHOUT PRESSING THE ACCELERATOR PEDAL like it should it's just the bulb. Change it.

[apple2005]

No, the OD OFF lamp DOES illuminate briefly when the ignition is first turned from off to run (before starting) for the bulb proveout check



Then you either have multiple bulbs out, or you aren't very observant :tongue:

The Airbag, seat belt, ABS (if equipped), Air Suspension (if equipped), Check Engine and the OD OFF lamps will ALL illuminate for a short period when you FIRST turn the ignition from off to run but not starting.


This is of course assuming you have an analog cluster. If you have the digital dash, the warnings on the cluster are VFD and rarely if ever go bad. There are also more warnings that will display during the prove-out period than an analog cluster (ie washer fluid, door / trunk ajar, etc.)



Try it again and see what lights up.

If the car is NOT down shifting to third from overdrive (depressing the button disables overdrive - illuminating the green OD OFF lamp, pressing it once again turns it back on) while cruising at free way speeds suspect the switch itself or switch wiring near base of shifter.

If the car is indeed downshifting when the button is depressed, WITHOUT PRESSING THE ACCELERATOR PEDAL like it should it's just the bulb. Change it.

Thanks drock96marquis for your detailed explanation.
Actually what I see in run(before starting) is check engine in yellow, which my garage told me that it is yellow because of oxygen sensors. If you want to change it will cost you a lot, better leave alone. 2) check air suspension in green 3) temp 4) gas level 5) battery in red 6) oil icon in red 7) others like kilometers to go, economy, trip etc.
Others than that no other light or indicator on my DIGITAL DISPLAY.
I don't know which other indicators should be there?