Sounds like the relay. It would be that if you're lucky. Check your fuses too. Make sure to get a really good look at them and test with a multimeter if you can, sometimes a fuse can still look ok when it's not. What kind of truck?
If i remember correctly something like a 95 F150. But would a fuse, cause the brake light to turn off when you signal?
I am not all that knowledgeable when it comes to automotive electrical but I doubt it would. They are easy to check, though. Knowing that the hazards still work should eliminate any bulbs or wiring problems. I do know that occasionally on those fords the multifunction can go bad but I think if that happens then you lose a lot of other things. That is also something I don't know a lot about. It might be possible to switch the hazard and turn signal relays and that would tell you if the one is bad.
aaaaand my truck is dead. CEL came on yesterday afternoon on the way home. "Hmm, that's odd. Better get that checked in the morning." It won't start this morning. I can turn the key and here the fuel pump prime, but none of the gauges respond. (battery is good, and I just filled up earlier this week, so both voltmeter and fuel gauge should move.) Also, the interior dome and map lights don't come on when I open the door, but the headlights will work, and I can get it to turn over just fine. For the entire life of this truck, it has started first time every time. I plugged in a code reader, and it will not get anything - display says it can't communicate. I tried a number of different ways, and I'm pretty sure I'm doing it correctly. I think I have some kind of computer / electonics failure, but I have no idea where to start. Anybody have any suggestions?
Did you disconnect any grounds? I know that, at least with in car electronics, if something isn't properly grounded that it won't turn on or work at all.
What do you mean that the gauges won't respond? I'd double check your battery, maybe try a different one. It turns over so it should be good but who knows. Knock sensors will cause a no fire. Maybe try disconnecting your battery for 1 minute to reset the computer. Check your fuses, GM links it's diagnostics port with other electrical stuff. The port needs power for a scan tool to work. See if it will fire with some starting fluid. Hearing your fuel pump doesn't mean it's building enough pressure and it only needs to be a couple psi low for an efi engine to not fire.
Okay, fuses are definitely something I need to look at, along with trying to start with ether. As far as "guages not responding" what I mean is this: normally, when my truck is off, the needles of all the gauges drop to the far left. Then, when I turn the key on, they'll move to display current value. Temp won't move right away, but fuel should jump up to over half full, voltmeter should move to about 14 (in the middle) and oil pressure would move up to about the middle. Obviously speed and tach won't do anything if it's not running or moving. Instead, when I turn the key, the dash lights come on an it's like they want to work, but . . . nothing. I did try disconnecting the battery to try and reset, before I left for the office, but that didn't work. I'll check the other stuff when I get home this evening. Thanks.
Kind of sounds like something in the ignition or maybe a bad PCM. The gauge pods in those trucks are known to go bad but the engines still run when they do. I don't know how other scan tools work but with mine I plug it in with the key off, let it do it's thing and then pick the vehicle and then turn the key on and hit read.
Might be a wire rub somewhere and there is a wire grounding out to the frame of the vehicle. Depending on how the lights are wired it might not draw enough current to blow the fuse. Do you mean with the hazards on and you signal, the brake light shuts off along with the hazards? Or just in general turn signal on, brake light goes out? Does the brake light come back on when the signal's turned off? I also agree with checking the flasher relay.
Awww yeah - file this in the "This shit can only happen to me" department. My truck has been at the dealer since last Thursday. This morning I get a call from the service department: Serv: I've got some bad news. Me: Great, I can't wait. Serv: Has your truck ever been struck by lightning? Me: <silence> I mean, come ON! So, apparently the PCM, the BCM, the radio, and the instrument cluster all shit the bed, due to "an unusual voltage surge." Supposedly, the shop tech who is their electronics specialty guy who's been doing this a long time said he's never seen anything like this before. Awesome, well of COURSE I'd like to spend $3000 on a truck that's maybe worth $7500.
Wow, that is crazy. If it's a $3000 bill I wouldn't fix it. I don't see that truck being worth $7500 with that amount of miles, it's so hard to sell really high mile vehicles.
Spent the last three nights after work fighting the dreaded lower intake manifold gasket on my beater '98 Tahoe. Thankfully, I didn't mess it up, although I was skeptical about getting the distributor back in properly. I replaced a bunch of other crap that needed it since everything was torn off the engine except for the heads. Why GM decided to put such a poorly designed gasket into one of their best selling engines (Vortec 5700) is beyond me.
Ah, yes, it may not be worth $7500. But, unrepaired it's worth about $50. Anyhoo, insurance company is picking up the tab, since it was a no-fault claim, either act of God or Government. Funny side note: I was on the phone talking to the adjuster, and he had just told me that it would probably be covered. He also had no explanation, and said lightning strikes usually have a burn mark or cluster of melted wires. I told him that someone suggested it was an EMP from a shadow government group - and his cell phone immediately went dead. We laughed when he called me back.
The crappiest part is that it was leaking for who knows long but didn't show any symptoms, other than slowly disappearing coolant. I swapped the water pump, radiator, all the hoses, everything looking for the stupid leak. Finally, it just started dumping coolant into the lifter valley. Hopefully, I caught it before any bearing damage was done.
That is the problem most people have. It is just a small coolant leak, they dont see any anywhere so they just leave it be. Too bad you didn't mention it in here, if you did, sorry i missed it. I would of said go pick up a Felpro MS98000T gasket set, change it, and it will solve all your problems. I carry a stack of different fixer gaskets just for the Chev intake problem. From what i remember there is a lawsuit going on between Chev and the makers off dexcool. Chev is blaming dexcool for the problem. That shit is completely different from any other antifreeze. When it first came out, you couldn't mix it with any other antifreeze or it turns to gel. All the green antifreeze now says you can mix it with any color, but when it first came out it was really really bad.
Somebody had a really bad day: <a class="postlink" href="http://rumors.automobilemag.com/report-first-c7-corvette-crash-204943.html#axzz2Ldd3Mhdk" onclick="window.open(this.href);return false;">http://rumors.automobilemag.com/report- ... z2Ldd3Mhdk</a>
I am a GM fanboy and I still hold to the idea that cheap gaskets and over-torquing of the heads from the factory caused all of the intake gasket problems. It still happens into the LS engine based trucks of today.