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Check Engine Light NOT coming on!

We have a 1996 Ford F-250 XL, dual gas tanks. Recently, it failed a smog check due to the fact that the Check Engine Light would not come on.



This car runs great, and in fact the emissions part of the smog test was normal, no problems at all.



Just would like some idea of what this could be - a burnt out light bulb, or fuse, or possibly computer (UGH) problem? What should we check first? Really wanna save this car as we love it! Thanks

I should add - the check engine light was working fine at last smog check two years ago.

Bulbs do burn out, even after only 14 years (sarcasm intentional).
Before you do anything else that might be more expensive, try replacing the bulb for your CEL.

As physicians are taught in medical school, "If you are in the US, and you hear hoofbeats approaching, think “horses”, rather than “zebras”.

In other words, whether you are diagnosing problems with humans or with machines, you should always try to eliminate the most obvious, most common cause of the symptom before you delve into the more remote possibilities.

The light should come on when you turn the key to “ON,” and it should go out after the engine starts.

If it NEVER comes on I’d suspect the bulb.

Most CELs ground through the ECM so if the first suspect bulb is good then there could be an ECM fault. Hopefully it’s the bulb.

There are about six codes related to the health of the ECM,you should scan and see if any exist, but if they did you would get a light, I am going to have to go with bulb also. This is a problem I have never seen. I have seen quite a few times the inability to communicate with the ECM through a scanner, but no “check engine” with the key in the “ON” position, not so familiar to me.

Sure the bulb is 14 years old but how many hours has it burned for, probably not many, pretty odd.

“how many hours has it burned for, probably not many, pretty odd”

Some professional reliability lore that says the bulb will get worn out by the on-off cycles it gets every time the car is turned on. That is, in some usage patterns the on-off cycling causes more wear than does constant on. Of course, that would apply also to the other warning lights (e.e., oil pressure) that get a self-test when the car is started.

As everybosdy has said, it is an unusual failure. But plausible.

fuse number 17 in the fuse panel is for the MIL. I would check that first before tackling the cluster.

F-250 isnt a “car” could be why the lights not coming on…

Still waiting for my husband to take a look at this… (big sigh)

Just out of curiosity…how hard is it to remove the dash in order to replace the CEL? Is this something we can do ourselves, or will it require a trip to the fix-it shop? I think my husband is dreading the idea of pulling the dashboard apart. Can’t say that I blame him.

A “Dash Monkey” (A mechanic who specializes in behind/under the dashboard repairs) can have the instrument cluster out and the bulb replaced in a few minutes…This repair is not a big deal…

One of my favorite words and practices is parsimony.
Stolen from wiki.
“Parsimony is the use of the simplest or most frugal route of explanation available.”

Oh boy. Checked fuse no. 17 and it is fine. Problem is, it’s a 15 watt fuse and that one is supposed to be a 10 watt. Looks like some knucklehead put in the wrong fuse. No wonder the light is burned out!

Thanks for all the advice.

What is your theory about how a higher value fuse caused a bulb to burn out?

OK, I just checked with my husband and I was wrong. A higher wattage
fuse is not the problem.

One last question: anyone know what a Ford dealership usually charges to pull the cluster and replace the bulb?

You don’t need a dealer to r&r the cluster to change a bulb just a decent mechanic. However I’d like to get back to this fuse. You say there is a 15 AMP fuse there and it’s only supposed to be 10 AMPs? That could Be an indication of your problem. The 10 amp fuse kept blowing so it was replaced with a higher amp fuse. Big nono. Never replace a fuse with a higher amp fuse. Chances are that you now have a melted wire somewhere.

I’ll be darned…my husband replaced one of the gas caps and the light came on. Then it went out again…just as we were pulling in to the Smog Check Station. Sigh. Then we drove home, and it came back on again.

So the bulb is there, it’s good, but now I’m thoroughly stumped. My husband thinks it might be a matter having to do with the gas cap and the vacuum in the tank (hope that makes sense) but why would the CEL show up sometimes, and fail to show up at other times? Could a loose wire be the culprit? We just want to get this @#$% car smogged! Thanks

I was so hoping for a finish to this thread. We have the same problem with our 2001 Ford f150, now. All the same symptoms, but as I just reading this, I have not checked the ECM fuse or #17. Don’t know what MIL stands for, but I can Google that. We had issues with the gauge cluster bulbs before, but solved that using extra bulbs in cluster. One problem we have is that as the CEL is not working, there is still a code showing that may or may not reset itself. So we need to solve the light problem first. The bulb has been checked as good, so we are at the fuse, wiring, or? Any more info would be much appreciated. Tyia. Btw… The code is for a problem with the gas sensor of some kind or fuel pump, but car starts and runs fine. No hesitation or stalling. Also we replaced battery cuz start of trouble was car wouldn’t start even with jump, but bypassing selenoid with a screwdriver jumped truck immediately. We’re not sure if doing that didn’t blow a fuse or short a wire. Visual of all fuses look fine, but we didn’t have a meter to test them better or the wiring… Sorry for long story, but easier to get to what we haven’t tried. Thnx.

unfortunately @bbryant hasn’t posted since their initial post 9 years ago. You could try clicking on their picture and selecting message…they would receive a notification sent to the email they originally registered with and could answer you.

Malfunction Indicator Light (same thing as the CEL)

So we don’t have people getting confused between your problem and the original poster’s problems (which may or may not be related), may I recommend that you place your post in a new topic by clicking new topic on the main page?

I actually have the same exact problem with my wife’s car.
Dodge Journey 2011 6 cylinder AWD. I took it for inspection and it didn’t pass because the check engine light is missing. And I honestly cant take it to a mechanic now cause I work in the field and it’s winter so there’s no work for me now. So I’m seeing if I can do it myself. If anyone knows. Please help.