Emission Light Question
Thread Starter
|
New User
Joined: Oct 2008
Posts: 11
Likes: 0
Emission Light Question
I'm sorry if this seems to be a heavily talked about subject, but I can't find the answer I'm looking for. I own an '86 F150 with a 5.0L EFI. My emission light just came on a few days ago. So, I'm trying to find the brown box that is used to reset the light and I can't seem to find it. Is this how you reset it on my truck, if so where exactly is it located or is there some other way to reset the light???
Moderator
Joined: Jan 2001
Posts: 56,992
Likes: 2,741
From: Virginia
Is it the check engine light? If so, you have a problem.
The CHECK ENGINE or SERVICE ENGINE SOON dashboard warning lamp is referred to as the Malfunction Indicator Lamp (MIL). The lamp is connected to the engine control assembly and will alert the driver to certain malfunctions within the EEC-IV system. When the lamp is lit, the ECA has detected a fault and stored an identity code in memory. The engine control system will usually enter either FMEM or HLOS mode and driveability will be impaired.
The light will stay on as long as the fault causing it is present. Should the fault self-correct, the MIL will extinguish but the stored code will remain in memory.
Under normal operating conditions, the MIL should light briefly when the ignition key is turned ON. As soon as the ECA receives a signal that the engine is cranking, the lamp will be extinguished. The dash warning lamp should remain out during the entire operating cycle.
The CHECK ENGINE or SERVICE ENGINE SOON dashboard warning lamp is referred to as the Malfunction Indicator Lamp (MIL). The lamp is connected to the engine control assembly and will alert the driver to certain malfunctions within the EEC-IV system. When the lamp is lit, the ECA has detected a fault and stored an identity code in memory. The engine control system will usually enter either FMEM or HLOS mode and driveability will be impaired.
The light will stay on as long as the fault causing it is present. Should the fault self-correct, the MIL will extinguish but the stored code will remain in memory.
Under normal operating conditions, the MIL should light briefly when the ignition key is turned ON. As soon as the ECA receives a signal that the engine is cranking, the lamp will be extinguished. The dash warning lamp should remain out during the entire operating cycle.
Thread Starter
|
New User
Joined: Oct 2008
Posts: 11
Likes: 0
Is it the check engine light? If so, you have a problem.
The CHECK ENGINE or SERVICE ENGINE SOON dashboard warning lamp is referred to as the Malfunction Indicator Lamp (MIL). The lamp is connected to the engine control assembly and will alert the driver to certain malfunctions within the EEC-IV system. When the lamp is lit, the ECA has detected a fault and stored an identity code in memory. The engine control system will usually enter either FMEM or HLOS mode and driveability will be impaired.
The light will stay on as long as the fault causing it is present. Should the fault self-correct, the MIL will extinguish but the stored code will remain in memory.
Under normal operating conditions, the MIL should light briefly when the ignition key is turned ON. As soon as the ECA receives a signal that the engine is cranking, the lamp will be extinguished. The dash warning lamp should remain out during the entire operating cycle.
The CHECK ENGINE or SERVICE ENGINE SOON dashboard warning lamp is referred to as the Malfunction Indicator Lamp (MIL). The lamp is connected to the engine control assembly and will alert the driver to certain malfunctions within the EEC-IV system. When the lamp is lit, the ECA has detected a fault and stored an identity code in memory. The engine control system will usually enter either FMEM or HLOS mode and driveability will be impaired.
The light will stay on as long as the fault causing it is present. Should the fault self-correct, the MIL will extinguish but the stored code will remain in memory.
Under normal operating conditions, the MIL should light briefly when the ignition key is turned ON. As soon as the ECA receives a signal that the engine is cranking, the lamp will be extinguished. The dash warning lamp should remain out during the entire operating cycle.
Senior User
Joined: Nov 2006
Posts: 203
Likes: 0
I hate that light!!! Mine is not on now, but I was told they come on from a timer basically, i would assume on hours? It is such a useless idiot light, it has no bearing on your emissions system, it just serves as a reminder
I am interested in how to reset it though for when mine comes on....
I am interested in how to reset it though for when mine comes on....
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Yep, the Emission Light is really useless.
It just reminds you to check the computer codes. The light will come on if you have a problem or not. Every 60,000 miles aproximately.
The check engine light wasn't introduced untill circa 1988.
It just reminds you to check the computer codes. The light will come on if you have a problem or not. Every 60,000 miles aproximately.
The check engine light wasn't introduced untill circa 1988.
Post Fiend
Joined: Nov 2005
Posts: 7,437
Likes: 4
From: Charles Town, W bygod Va
You're supposed to do a check on certain sensors before you reset the light, back when these were new, shops would charge 1-2 hrs labor to reset the light. It's a bunch of BS tests before OBD1 was used
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
The MCU with Duraspark-II, the EEC-III with Duraspark-III and EEC-IV with TFI-IV ignition are all OBD-1 systems.
The Computer diagnostic was a part of the test, when the emission light came on. If there was a problem or not. The emission light is not connected to the OBD-1 type computer whatsoever, it's on a timer.
It was really a bunch of BS alright.
Trending Topics
Post Fiend
Joined: Nov 2005
Posts: 7,437
Likes: 4
From: Charles Town, W bygod Va
UR probably right on the obd1 thing..it was just part of the evolution of OBD. The early ones were very primitave by current obd2 standards
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
Freshman User
Joined: Dec 2007
Posts: 45
Likes: 0
I found this thread from shortly back, so I figured I'd just tag on to this. How is the emissions light reset? Mine came on and rather than remove the bulb, I'd like to know how to reset this if possbile.
Thanks.
Thanks.
Elder User
Joined: Apr 2003
Posts: 673
Likes: 0
From: Maryland
Do a search, I seem to rember it having a reset switch. The brown box was above the headlight switch on my '85. The PO of my '86 went to the trouble of covering the lamp with rubber tape hide it when selling the vehicle. When I pointed it out, "Looks like trouble", it made a nice dent in his asking price... 
Dummy!
Dummy!
Thread
Thread Starter
Forum
Replies
Last Post
4caster
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
3
Jan 2, 2010 09:50 PM
drubio07
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
1
Feb 28, 2009 10:40 PM
riyo2008
Explorer, Sport Trac, Mountaineer & Aviator
3
Aug 4, 2008 11:43 PM
