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Topic: I have no check engine bulb even a bulb socket?! (Read 3190 times) previous topic - next topic

Re: I have no check engine bulb even a bulb socket?!

Reply #15 –
well test lights shouldn't be that expensive. if i remember mine was only 5 bucks i belive. but  i would have no clue on how to actually make one.
2001 Buick Regal LS (DD):hick:

Got that fox rash again!

-Resident smartass! :ies:

- Don't listen to the naysayers. For every person who actually helps with your project there will be 10 who will discourage you all the while thinking that they are helping. 99% of all people have good intentions. That doesn't make them right.- XR7 Dave - SCCOA.Com

Re: I have no check engine bulb even a bulb socket?!

Reply #16 –
If this'll work, I can make one for free from my wiring kit and this light. I just need to know if jumping the small plug to the upper right (if the large test plug has the smaller side facing up) of the big plug will light the light in the same way the check engine light works.

Re: I have no check engine bulb even a bulb socket?!

Reply #17 –
thunderchicken or masterblaster have the diagrams for this i remember it cuz it was on the old boards.
2001 Buick Regal LS (DD):hick:

Got that fox rash again!

-Resident smartass! :ies:

- Don't listen to the naysayers. For every person who actually helps with your project there will be 10 who will discourage you all the while thinking that they are helping. 99% of all people have good intentions. That doesn't make them right.- XR7 Dave - SCCOA.Com

Re: I have no check engine bulb even a bulb socket?!

Reply #18 –
Quote from: Bird351
If this'll work, I can make one for free from my wiring kit and this light. I just need to know if jumping the small plug to the upper right (if the large test plug has the smaller side facing up) of the big plug will light the light in the same way the check engine light works.

I'm not sure if I'm reading your post right, but... look here and scroll just under half-way down to the test hookups illustration. Make sense? Some wire and a 12V light will work. That illustration should make it pretty clear. I'd buy a $15 buttstuffog multimeter myself. They're useful for TPS, O2 sensor testing and many other things.

Re: I have no check engine bulb even a bulb socket?!

Reply #19 –
Like I said, I'm not buying a second multimeter if I can avoid it. The digital one serves me well.

I've seen those diagrams before. The method I used for the check engine light wasn't shown on the first two. I just made a 1-2" piece of wire with two blade connectors on it, to jump between SIG RTN and STI. What I was asking is if it's possible to make a second jumper like that, but instead of a piece of wire, using a low-power light instead. It would be similar to the first diagram with the test light, except not running to the positive battery terminal.. just the little connector wire. Make more sense?

Re: I have no check engine bulb even a bulb socket?!

Reply #20 –
Quote from: Bird351
Make more sense?

No.
To the best of my knowledge, the STO switches between ground and no ground to show codes. Your test light will need a power source, which is the reason you hook it up to the battery. If you hook up a light to "just the little connector wire" it will never light up.

Re: I have no check engine bulb even a bulb socket?!

Reply #21 –
I'm not talking about putting a light on the STO.

Here:

EDIT: I forgot, I had intended to eliminate the STO part of that diagram to better illustrate what I was asking about.

Re: I have no check engine bulb even a bulb socket?!

Reply #22 –
Port #2 is just the "trigger" port. It doesn't actually do anything besides tell the ECU to send codes by pulsing port #4 to ground, so no, you can't use one device to do the job of two.  :grinno:
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

Re: I have no check engine bulb even a bulb socket?!

Reply #23 –
So is this little light going to survive if I hook a wire to it long enough to contact the positive battery terminal, and put it in the STO? I get a little nervous about hooking things right to the battery without fuses and what not.

Re: I have no check engine bulb even a bulb socket?!

Reply #24 –
Quote from: Bird351
So is this little light going to survive if I hook a wire to it long enough to contact the positive battery terminal, and put it in the STO? I get a little nervous about hooking things right to the battery without fuses and what not.

Yes.
There is no need for a fuse. The STO is simply switching between ground and no-ground.
The circuit looks as follows:

(battery) 12V------(light)------0V (STO grounded)
(battery) 12V------(light)------12V (STO not grounded)

Ohm's law states Voltage = Current (Amps) * Resistance (Ohms) V=IR
You can rearrange that to I=V/R
Say you ran a small bare wire (With a resistance of .001 ohms) from the positive battery connector to a chassis ground.
I=12 Volts / .001 ohms = 12000 Amps
As you made the connection, sparks would ensue and the wire would most likely overheat and burn into two pieces.
For the next hypothetical case, you run a small bare with with a 12V light (150 ohms) inline between the positive battery lead and a chassis ground.
I=12 Volts / 150 ohms = .08 Amps
Much more reasonable.
As long as no short develops in the system with the 12V light, the system can never draw more than .08 Amps.
Make sense?