Check Engine light but no fault codes present

[JMac4506]

Hello!
Anyone have their Check Engine light come on but when readers connect to OBD port, no fault present.
I used two different code readers to see if results the same.
Yep... both systems say no fault code present, but yet the check engine light stays on.
Some history prior... I had just replaced tail light/ turn signal bulb with LED bulbs.
Turn signals work fine...
Just weird...

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[JW in Dixie]

What make and part # LED bulbs did you use, please. Would like to change mine. Thx

 

[cdf912]

JMac4506, did you disconnect the battery for at least 30 min when you changed out the bulbs? If you didnt, disconnect it for 30 minutes minimum, clear the CEL, then see if it comes back. May take 10-15 drive cycles before the CEL lights again, if it does.

 

[JMac4506]

Will check it out.
I also have a couple other plans of attack. I purchased standard tungsten filament bulbs to put back in to see if CE light goes out.
Also looking at replacing flasher relay or adding one of those limiters to the circuit!
Funny, I'm doing an awful lot of work just to get out of ever having to change a bulb again! LoL

 

[JMac4506]

Disconnecting the battery's negative pole worked perfectly! Thanks CDF912! I went ahead and installed new headlamps and the LED parking light/turn signals prior to pulling negative post. I'm good to go now!

Also... I found this web site that has some pretty good information.
Check it out!
https://www.carcarekiosk.com/videos/Ford/Thunderbird/2004

 

[JMac4506]

What make and part # LED bulbs did you use, please. Would like to change mine. Thx

I picked these up-

WHITE- https://amzn.to/34tY9vG

AMBER- https://amzn.to/3orDKzl

The amber for the front and white for the tail lights.
Remember to watch for bulb polarity. Unlike standard tungsten filament bulbs, you have to check which way you install.
Also... one more thing I will be watching...
There seems to be a very minor power drain with these bulbs. Meaning, even with vehicle turned off, there is a very faint glow coming from the bulbs. Will watch this a few days and make sure it doesn't affect car battery life.
The bulbs ran me $20 a set... But I look at it this way... I'll never have to replace them again!

 

[OREOCAT]

Take the blade switch and lift the lever. Replace the lever. That should work.

 

[JMac4506]

What make and part # LED bulbs did you use, please. Would like to change mine. Thx

Well JW... I have my tail lights all wired and switched to LEDs. Have also gotten the CE light to stay off from the LED lamp issue.
Bit of a pain in the ass and I want to watch it a while before converting the front lights as well.
I had to use 2 of those 50watt resistors on each lamp. (One for turn signal/Brake light and one for the running lights)
My only concern is the resistors got pretty warm, as they should under load. I want to give these a week or so and see if the temperature gets to a point of melting any of the plastic in my tail light assemblies.
So in order to change the light s over AND keep the CE light from coming on, you will need 8 of those resistors.
Will let you know in a week if the heat doesn't seem to be an issue.

 

[JMac4506]

What make and part # LED bulbs did you use, please. Would like to change mine. Thx

Well guys... I HAD LED lights for one day. It seems my resistor heat concern had merit.
In just one evening of driving, start stop traffic, turn signals, waiting at stop lights...
The resistor for the turn signal become so hot it melted into my tail light assembly.
So please DON'T add these to your car unless you run some very long wires and can mount the resistors in a location that does not mind heat!!!!
I cut the resistors out and put the filament lamps back in 🙁

 

[Netconn]

I do believe you need to mount those resistors on the metal where the heat can be transferred to the metal. They will generate a lot of heat.

 

[JW in Dixie]

Could you connect the parking LEDs in series to drop the voltage? Would a Zener diode work in this application? JW

 

[U5512]

Only buy and use "CANBUS ERROR FREE" LED light bulbs as they have resistors built into the units, and the lights will go out when you turn them off (no faint glow 24/7).