I'm going to start off with. I already checked the fuses, they all look good.
The headlights will turn on, but they wont close. Every single other light isn't turning on at all though. No side markers, no tail lights. The brake lights wont turn on either. I actually didn't check if the reverse lights work or not. Does anyone have any clue as to what could be going on here? What else should I look at. The car sat for about a month and a half, almost 2 months because I needed a new crank position sensor. I also replaced the alternator while I waited on the sensor. I also have a new battery. Good thing is that it runs now.
Any thoughts? I want to go on night cruises safely.
What year Fiero, that matters. Without that.... fusible link?
Its a 1988 notchback. 4 cylinder. I'm still fairly new to cars. But I'm pretty sure I can take a look in the morning and see if any of those are bad. Do you know where they would be at specifically?
Out of curiosity, when you turn on the headlight switch to parking lights, with the key or of the ignition, does the blue dingy thingy start chiming? All of this definitely sounds like a fuse or fusible link, having the brake lights not work too as another layer of complexity.
Did all of this start happening at the same time? Did they work for a second then stop working, did the brake lights stop working at a different time then the rest?
Out of curiosity, when you turn on the headlight switch to parking lights, with the key or of the ignition, does the blue dingy thingy start chiming? All of this definitely sounds like a fuse or fusible link, having the brake lights not work too as another layer of complexity.
Did all of this start happening at the same time? Did they work for a second then stop working, did the brake lights stop working at a different time then the rest?
Just looked. There's no chiming. But it kinda stopped at the same time. Sort of. It started off as the indicators weren't indicating. And then the rest just stopped
There are two wires from the chassis harness that connect to the Battery Junction Terminal. The chassis harness is the bundle of wires alongside the battery in the plastic sleeve. One wire is red, the other wire is red/white. The red/white wire supplies power to the light system.
Okay I'll take a look here in a bit. On a side note though, I'm not quite sure what happened and I won't complain. But the indicators work now. Still no brake lights and like, uhhh. I'm not sure what the proper term for it is. Running lights?
I would suggest that you disconnect the battery in positive lead, pull the wires from the BJT and clean everything well and reattach the wires and hook up the battery.
It won't help solve your problem, but it will ensure good voltage transfer at that connector.
It's not hard. Disconnect the battery. Take the wires off of the BJT. Clean the corrosion off of the wire ends and the terminal posts. (Sandpaper, wire brush etc) (The two posts are connected together inside the terminal) Hook everything back up. Done.
Your headlights go up, do the bulbs turn on? If they do, you may have a problem with the headlight switch.
It's not hard. Disconnect the battery. Take the wires off of the BJT. Clean the corrosion off of the wire ends and the terminal posts. (Sandpaper, wire brush etc) (The two posts are connected together inside the terminal) Hook everything back up. Done.
Your headlights go up, do the bulbs turn on? If they do, you may have a problem with the headlight switch.
Okay fair enough. But yes the headlights go up, and turn on. But the headlights won't go back down. But it will turn off
Link A to red wire is nearly everything in the car just including brake/turn/parking & other lights lights. IOW Almost Nothing will work including the engine if that link dies. Link B to red/wht wire is only Headlights. So If HL Bulbs are On, Is Not a link.
Cleaning the Junction Box won't help this issue but often helps a lot of other wiring problems. Clean then coat w/ silicone or permatex green label brake grease. Use a very thin film on the metal parts.
If all other front & rear parking lights are "dead" likely the HL Switch has failed for parking lights. Plus that also put HL Down. Try pushing only the park side of switch first.
but also said no brake/turn light too may mean rear lights have more then "bad HL switch" like may have crap ground in back of car. Pull the fixtures, find ground from any bulb socket then jump that wire to the metal & see if any brake/turn light works. Push a pin in the back of a socket to hit the the metal end or the ground wire then ground that pin. If pierce the wire, coat the hole w/ tiny bit of "bulb grease" off a bulb or silicon to seal out water.
If some works other(s) not then can have iffy sockets or bulbs. See cave light bulb & sneak path
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
Troubleshooting can be a daunting task, and there are many ways to approach it.
Up to you how you get this resolved,
You could go replace a bunch of components and might get lucky.
You coul do some maintenance - electricity hates corrosion. Don't ignore the green on the connectors and mind your grounds. Plausible giving the synopsis you're providing thus far.
Break the system out into portions, the battery is the only source of power without the alternator running. You can work your way through the circuit and find the problem by going step by step.
So I did take out the switch. It does look pretty burned. And one of the little "pin" things aren't fully reaching the part it needs to. So I did order a new one and hopefully that should fix my parking light and headlight situation.
When it comes down to the brake lights. I can't find the ground wire you guys are talking about. I get the feeling that one of the previous owners tried to do some rewiring before. Unless I'm just crazy.
What color is the ground. And where should I be tracing it back to? I'm so lost here...
I apologize as I'm still new to working on cars and this being my first car.
I took a look at the ground. It looks completely fine. I still took it off, cleaned. But there wasn't any corrosion by the look of it. Do I need to take the ENTIRE thing out? Every connector looks fine. The wires for the most part look completely fine. At least the wires that aren't all taped together and such.
I got the headlight switch coming in so it could be the problem.
Brake light power is as follows... STOP/HAZ FUSE - ORANGE WIRE TO BRAKE SWITCH - LT BLU WIRE TO HIGH LEVEL STOP
BRAKE SWITCH - WHITE WIRE TO TURN/HAZARD SWITCH ASSEMBLY - YELLOW WIRE TO LEFT BRAKE LIGHTS DK GREEN WIRE TO RIGHT BRAKE LIGHTS
Your STOP/HAZ FUSE could be blown check the fuse with a meter-dont visually inspect it) Your BRAKE SWITCH could be bad (does the plunger move? It's easy to take apart and clean) Your TURN/HAZARD SWITCH could be bad (it's in the column) The pigtail from the column could be unplugged
Brake light power is as follows... STOP/HAZ FUSE - ORANGE WIRE TO BRAKE SWITCH - LT BLU WIRE TO HIGH LEVEL STOP
BRAKE SWITCH - WHITE WIRE TO TURN/HAZARD SWITCH ASSEMBLY - YELLOW WIRE TO LEFT BRAKE LIGHTS DK GREEN WIRE TO RIGHT BRAKE LIGHTS
Your STOP/HAZ FUSE could be blown check the fuse with a meter-dont visually inspect it) Your BRAKE SWITCH could be bad (does the plunger move? It's easy to take apart and clean) Your TURN/HAZARD SWITCH could be bad (it's in the column) The pigtail from the column could be unplugged
Brake switch plunger. That's that thing that's "pressed up" against the side of the brake pedal. Little white box with a thing sticking out of it.
If that's what you're talking about. Yeah I took a look at that already. Nothing is wrong with that, moves completely fine no problem.
The turn switch actually works now. Idk what I did to fix it. But yeah that works. And all the lights will blink
I'll check the pigtail thing here in a second. I'll also check the fuse again
But when I tested the TAIL fuse. And the STOP/HAZ fuse. Only one side of the fuse was working. If that makes sense
All of the other fuses were good. And I used a volt meter.
What do you think that could be?
One side of a fuse can't be good. With that said, only one side of the fuse socket will have power - if the fuse is good, it sends the power to the other connector on the fuse socket.
I would suggest replacing both fuses for starters.....
One side of a fuse can't be good. With that said, only one side of the fuse socket will have power - if the fuse is good, it sends the power to the other connector on the fuse socket.
I would suggest replacing both fuses for starters.....
So. I still haven't got my headlight switch. But I was at a hardware store and decided to try new fuses.
That fixed it. I just bought new ones and its odd, the old fuses look completely fine. Almost "brand new", but hey. It worked
I'm going to start off with. I already checked the fuses, they all look good.
The headlights will turn on, but they wont close. Every single other light isn't turning on at all though. No side markers, no tail lights. The brake lights wont turn on either. I actually didn't check if the reverse lights work or not. Does anyone have any clue as to what could be going on here? What else should I look at. The car sat for about a month and a half, almost 2 months because I needed a new crank position sensor. I also replaced the alternator while I waited on the sensor. I also have a new battery. Good thing is that it runs now.
Any thoughts? I want to go on night cruises safely.
That's your first post in this thread.
If you had known how to properly check a fuse, you would have saved yourself, and others, a lot of time.
Next time you ask for help, be POSITIVE you are providing CORRECT information.
Glad it works. Never trust a fuse by its looks. Always use a meter and check continuity through the fuse.
Fuses can test good by a continuity check, but not be able to carry power.
I spent a long time chasing a fan circuit and all of the possible causes for not running, when a neighbor asked if I had changed the fuse. I said that the fuse looked good and I had checked the continuity, when he quickly suggested I change the fuse. The fan worked instantly, followed by an explanation that visual or continuity tests are not always accurate.
Fuses can test good by a continuity check, but not be able to carry power.
I spent a long time chasing a fan circuit and all of the possible causes for not running, when a neighbor asked if I had changed the fuse. I said that the fuse looked good and I had checked the continuity, when he quickly suggested I change the fuse. The fan worked instantly, followed by an explanation that visual or continuity tests are not always accurate.
That's a very rare occurrence. If there is continuity, current can flow.
How do you think a continuity test works? If a 9 volt meter can show continuity, you can bet that 12 volts will flow.
Another way to test would be to probe both sides of the fuse while still in the panel, but that's a lot more difficult to perform.
[This message has been edited by olejoedad (edited 04-28-2024).]
That's a very rare occurrence. If there is continuity, current can flow.
How do you think a continuity test works? If a 9 volt meter can show continuity, you can bet that 12 volts will flow.
Another way to test would be to probe both sides of the fuse while still in the panel, but that's a lot more difficult to perform.
Rare, but real.
What happens is that the fuse breaks under load. When it cools, contact is made, but then under load separates again. In my example, the fan would try to turn, but instantly stop because the current created heat that bends the fuse element. It is the same way a bimetal turn signal switch works; making contact to illuminate the light and bending to disconnect and reconnecting when cooled, repeating until the switch is turned off.
When this happens with a fuse, it is referred to as a "hanging fuse".
When the continuity check is made , the fuse is cool, using a low voltage and without a load. This can result in a reading of a fuse having continuity, but doesn't test under working load. Testing fuses in the panel, probing for working voltage on both sides of the fuse while under load, as you suggest, is the best way to avoid being misled by the rare hanging fuse condition. This method will also verify that the wiring from the power source is good and if the power is getting through the fuse under load.
Odd thing is that it genuinely was the first thing I checked. I went through everything with a volt meter and with the car on.
I also double checked
When I first did all of it both sides worked, so I don't know how it ended up like that... Either way, they work now. But I truly do appreciate how helpful you've been. Despite my lack of knowledge with cars. You have no clue how much your help means to me. Thank you
Odd thing is that it genuinely was the first thing I checked. I went through everything with a volt meter and with the car on.
I also double checked
When I first did all of it both sides worked, so I don't know how it ended up like that... Either way, they work now. But I truly do appreciate how helpful you've been. Despite my lack of knowledge with cars. You have no clue how much your help means to me. Thank you
You are very welcome. It's frustrating to figure out problems when you're just learning about cars. We are always here to help, no matter how difficult the problem.
⚠️ Warning: Only buy known brands of fuses like Bussmann, Littelfuse, etc. While big brand likely cost < a penny to several pennies to make & package most car fuses, many others still make way cheap fuses that fail to meet any safety standards & fail to blow when needed or blow way easier.
ATC like Fiero uses, ATM many new cars uses & related "Blade" & other plastic fuses can fail like 87GT3800SC5SPD said or just fail as temp changes or vibration so may fail in 1 sec & pass the next sec. The plastic can hind tiny fractures/defects in the metal section & unless fuse carries enough Amps, often does not "cook" the part. IOW Cracked 20a Fuse won't cook running a few light bulbs, more so because 100% resistive load not inductive load like a blower/fan motor.
Part of why is many are 1 piece stamp metal then plastic is injection molded or press on the metal then fuse section cracks for whatever reason but plastic holds the parts tight.
ATC & some others allow testing without pulling them. Is why there are many "testers" w/ 2 "pins" to get at the top of fuse & "light" is On when across a blown fuse. But this often fails to Light when have above happens.
Bulb Grounds isn't just the wire to the socket. Bulb itself or socket can be bad have same results of bad wire ground. Example: Any "Bayonet" sockets often have iffy connect w/ the base of bulb, more so w/ GM sockets in the back of Fiero because tiny ground "ears" get bent or other damage easily. Again, see cave light bulb & sneak path pages.
NAPA & some others sell 2057 etc in 10 packs that's way cheaper then 2 packs sold everywhere. I would replace all front & rear park/turn/brake bulbs as part of fixing this problem to stop guessing that 1 or more bulbs have problems. Do Not remove the bulb grease & add a bit more if needed. "Dirty" bulb grease is just fine because only keep water out unless super bad & dirt make bulb hard to replace.
Often the "Best Deal" on fuses are multi packs w/ several common values w/ or w/o a tester/puller like said above. If you think you need 2 values to replace, the "kits" get way cheaper then buying 2 to several single value pack.
