- that would be the first thing I would check.
Check engine light won't come on......
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From: Elyria, Ohio
Check engine light won't come on......
Tried to get the car inspected but they told me the check engine light won't come on. Several days ago I discovered one of the 5a central control module fuses blown. This was just after I washed it. Don't know if that's relevant or not; Knowing they're sensitive to water, I'm sure nothing got wet under the hood. Anybody know if this is a D-I-Y job to fix? I have no electronic equipment to diagnose the problem with. Where do I start looking?
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There is a good chance that the previous owner pulled the bulb so the light would not come on all the time.
This is fairly common.
This is fairly common.
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Thanks, guys...I'll check that possibility put. I just hope I don't have to disassemble half the dash to get to it. You know how that can go. Ever see how a radio comes out? Anyway, I hope that's it but I'm a little skeptical. It passed inspection last year. Maybe they just missed it then. Or maybe it just burned out? Wishful thinking on my part!
I'll check it out and see what I can see.................
I'll check it out and see what I can see.................
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To get to the lamp, you will have to remove the center console cover, loosen shifter plate, and remove radio bezel. The DIC (light panel) then comes out with a few screws. The bulb is then easy to get to.
There are 3 CCM (5 amp) fuses. Which fuse number was bad?
I also have a hard problem understanding how you could even get it started and have it run if even one of the fuses was blown. But since I never tried this scenario, I'll keep an open mind on this for now.
However, the check engine light (MIL lamp) is connected to and is a function of the PCM. So if the check engine light is not on, the bulb might be bad or there is a code in module 4 (which would keep it on) of the PCM. The CCM is not directly connected to the light. The CCM displays its problems as "SYS" in the speedometer (module 1).
There are 3 CCM (5 amp) fuses. Which fuse number was bad?
I also have a hard problem understanding how you could even get it started and have it run if even one of the fuses was blown. But since I never tried this scenario, I'll keep an open mind on this for now.
However, the check engine light (MIL lamp) is connected to and is a function of the PCM. So if the check engine light is not on, the bulb might be bad or there is a code in module 4 (which would keep it on) of the PCM. The CCM is not directly connected to the light. The CCM displays its problems as "SYS" in the speedometer (module 1).
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pcolt, The car wouldn't start at all......just a faint "clunk" from somewhere under the hood. Only after I methodically checked fuse by fuse did I find the blown one. It was #39. According to the book, #35 and #39 are just labelled "CCM". #16 is CCM and "daytime running lamps".
It doesn't dound as if removal will be too bad. Maybe it is just a burnt out bulb (yeah, wishful thinking
)
FWIW, the car doesn't run bad; the check engine light would come on if something were wrong, but it doesn't come on when you go to start the car. That's why they failed it. Only 41,000 on it but bulbs can go at any time of course. I think I may spend an "enjoyable" evening with the parts of the console tonight.......
It doesn't dound as if removal will be too bad. Maybe it is just a burnt out bulb (yeah, wishful thinking
)FWIW, the car doesn't run bad; the check engine light would come on if something were wrong, but it doesn't come on when you go to start the car. That's why they failed it. Only 41,000 on it but bulbs can go at any time of course. I think I may spend an "enjoyable" evening with the parts of the console tonight.......
Last edited by Vetteblack-96; Mar 16, 2014 at 07:03 PM.
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OK, it sounded like the engine was running. Now that I know it was not, it makes normal sense.
Fuse 39 is the main12 volt power for the CCM. Without the CCM working, all bets are off. VATS, FEDS, starter, all CCM functions and interaction with the PCM will not function. And of course the MIL light will not work.
Before you tear into it, make sure fuse #27 is good. That is for the check engine light.
Also check fuse #30, its the main voltage feed for #27 and other functions.
Fuse 39 is the main12 volt power for the CCM. Without the CCM working, all bets are off. VATS, FEDS, starter, all CCM functions and interaction with the PCM will not function. And of course the MIL light will not work.
Before you tear into it, make sure fuse #27 is good. That is for the check engine light.
Also check fuse #30, its the main voltage feed for #27 and other functions.
Last edited by pcolt94; Mar 16, 2014 at 10:01 PM.
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pcolt94, I think I'll go through all the fuses one by one again. I know for a fact that they are the correct amperage. I made sure of that the first time I checked. The check engine light (service engine soon - same thing, right?) should light up with the rest of the driver info when the key is turned to "on", correct? Then go off when turned to start? This might seem really basic but the car never had any problems before and as a consequence, I never leaned anything the hard way, so I have no experience to fall back on.
Thanks for your guidance!
Thanks for your guidance!
Last edited by Vetteblack-96; Mar 17, 2014 at 01:02 AM.
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From: Orlando FL
pcolt94, I think I'll go through all the fuses one by one again. I know for a fact that they are the correct amperage. I made sure of that the first time I checked. The check engine light (service engine soon - same thing, right?) should light up with the rest of the driver info when the key is turned to "on", correct? Then go off when turned to start? This might seem really basic but the car never had any problems before and as a consequence, I never leaned anything the hard way, so I have no experience to fall back on.
Thanks for your guidance!
Thanks for your guidance!
Right, will stay on when key is on and engine not running.
Right, the engine has to start and run for the light to go off.
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From: Elyria, Ohio
Just an update. I seem to have fixed the problem. I read something somewhere that the car could sense a fuel cap not closed tightly. Not too sure if that's true but I opened the cap and reclosed it until the ratcheting sound was heard. Started the car in the normal way and the light worked in the normal way. Was is just coincidence that the light worked then or did the "loose" cap have anything to do with it? Wouldn't the "service engine light " come on if it did sense a problem? The inspector said the light wouldn't come on. I just took him at his word at the time but now I'm starting to wonder if his light didn't come on................