Re: 86 bronco emmission light
I am attaching this info on how to reset the light. It should print out all right,
The module you are looking for is listed as Item C550. In the 1986 literature, it is called an Emission Maintenance Warning (EMU) module. It is also referred to as an Inferred Mileage Sensor, or an Extended Useful Life Sensor. Its function is to measure when 2000 hours of operation have been reached. The mechanic is instructed to look over the emission system, but no specific work or replacement of parts is advised or required in the manual. I am looking at the Ford FPS-126-326HL Engine/Emissions Diagnosis Manual, volume H, for 1986 cars and trucks. If things look OK, mechanic resets the module. This is also done whenever any emissions work is done of the truck, so may not hit at 2000 original hours or 60,000 original miles.
The easy way - put a piece of black electrical tape over the light
The right way per Ford:
To find the module:
It is a little black plastic module behind the dashboard located on a metal bracket between the steering column and the windshield wiper switch. Looks about 1 inch wide, 2 inches tall, and connector on the top. It is solidly mounted to a bracket with a couple of screws, so it can be removed to make things easier.
To see it, you will need to rig the door so that the dome lights/foot lights do not come on - if you don't you will look right into a burning lamp.
Take a flashlight and hand mirror to find it. With the mirror up under dashboard on left side of steering column, shine light into mirror toward the backside of panel.. You should see the module. You will not see any hole or reset label on the side you can see. It is on the side of the module away from the steering column, near the top. I saw what looks like a white blob of paint, says reset under it. My guess is that you punch through the white blob with the Phillips screwdriver. Doesn't look too easy, you may need someone to help with the ignition switch part that follows.
Here are the exact Ford instructions:
Step 1. Turn ignition keyswitch to Off position
Step 2. Lightly push a Phillips screwdriver through the 0.2 inch diameter hole with the sticker labeled "RESET" and lightly press down and hold. Go to Step 3
Step 3. With the screwdriver still pressing down, turn ignition switch to the RUN position. The EMW lamp will then light and should remain lighted for as long as screwdriver is pressed down. Hold the screwdriver down for 5 seconds. Go to Step 4.
Step 4. Remove the screwdriver The lamp should go out in 2 to 5 seconds indicating a reset has occurred.. If not, start over at step 1. Turn the ignition switch to OFF and go to step 5.
Step 5. Turn the ignition to the RUN position. EMW Lamp should go off in 2 to 5 seconds. If not, repeat the procedure.
Personally, if it does not work by this time I will be looking for the tape. The book also says that some modules do not have the reset hole, and would need to be replaced. Removing the connector will also turn off the light.