DD won't start. Any clues? (maybe electrical short)
#81
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I just got back from load testing my battery, it's good for load, amps, and voltage, it's still at 12.6v right now.
so okay, how come with the miata battery hooked up, if I try to crank the car without the 12v lead to the starter hooked up, all is well, no power cuts out. But when I hooked the power wire back up to the starter solenoid, and tried it again for the video, the power cuts out and I cant restore power until I disconnect and reconnect the battery.
also, why does it take so long for the voltage to drop when I unplug it?
so okay, how come with the miata battery hooked up, if I try to crank the car without the 12v lead to the starter hooked up, all is well, no power cuts out. But when I hooked the power wire back up to the starter solenoid, and tried it again for the video, the power cuts out and I cant restore power until I disconnect and reconnect the battery.
also, why does it take so long for the voltage to drop when I unplug it?
#87
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I had a cold air intake and exhaust on it at one point. i learned to autox on it and blew most others in my class away.
it also ran a 15.7 in the 1/4 mile.
now fix my street/track car.
it also ran a 15.7 in the 1/4 mile.
now fix my street/track car.
#90
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Take the fuse box apart, and check.
I'm getting frustrated looking for pics/info on a car that is not in front of me. There are so many pics, and I don't know what yours looks like.
Forget battery. Forget solinoid.
You have a cable/wiring problem.
Have you performed the test I suggested?
This will tell me some info to help diagnose.
#93
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Clip both the red and black jumper cable ends to the negative battery terminal. With the other end, put one clamp on a good engine ground and one on a good chassis ground.
Fix it?
Yes... Good, put a good ground on it.
No... Try doing the same with the positive, but put the clamp on the starters main terminal and the other to the fuse boxes main junction bolt if it has one.
Fix it?
Yes...Sweet, fix a power wire.
No... Haul it to a shop and let them sort out the mess.
If this helps solve your problem, you should give me some love with a few free months of subscription...
Fix it?
Yes... Good, put a good ground on it.
No... Try doing the same with the positive, but put the clamp on the starters main terminal and the other to the fuse boxes main junction bolt if it has one.
Fix it?
Yes...Sweet, fix a power wire.
No... Haul it to a shop and let them sort out the mess.
If this helps solve your problem, you should give me some love with a few free months of subscription...
![big grin](https://www.miataturbo.net/images/smilies/biggrin.gif)
#94
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Clip both the red and black jumper cable ends to the negative battery terminal. With the other end, put one clamp on a good engine ground and one on a good chassis ground.
Fix it?
Yes... Good, put a good ground on it.
No... Try doing the same with the positive, but put the clamp on the starters main terminal and the other to the fuse boxes main junction bolt if it has one.
Fix it?
Yes...Sweet, fix a power wire.
No... Haul it to a shop and let them sort out the mess.
If this helps solve your problem, you should give me some love with a few free months of subscription...![big grin](https://www.miataturbo.net/images/smilies/biggrin.gif)
Fix it?
Yes... Good, put a good ground on it.
No... Try doing the same with the positive, but put the clamp on the starters main terminal and the other to the fuse boxes main junction bolt if it has one.
Fix it?
Yes...Sweet, fix a power wire.
No... Haul it to a shop and let them sort out the mess.
If this helps solve your problem, you should give me some love with a few free months of subscription...
![big grin](https://www.miataturbo.net/images/smilies/biggrin.gif)
This is a good test as well, and easier.
#98
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Scott, where does your battery (-) cable terminate?
Have you checked if that connection is good?
Also, have you checked your engine ground strap?
Since you have a DMM, just check and see what sort of resistance you have between:
* Battery (-) and engine block (with the (-) cable in place, of course)
* Engine block and chassis
* Battery and chassis.
Do these checks with the key off and key on engine off.
You should not see anything more than 0.1 ohms.
If you see high resistance in any of these tests, clean and re-check the grounds.
Also, set the DMM to measure draw (amps) and remove the battery (+) cable. Hook up one lead of the DMM on the battery (+) terminal, and the other lead on the (+) cable you have removed from the battery terminal.
Do this test with the key off, and key on, and post the results please.
Also, I am not very familiar with Nissans. Do they have a central circuit opening relay like Toyotas do?
You can also eliminate bad/coroded/shorted switch issues by hooking up a lead with an alligator clip on the starter solenoid. Just touch the other end of that lead on the battery (+). The engine should crank. (please remember to leave it in neutral)
Now, turn the key on, and touch that lead again on the battery (+). What happens then?
(Theoretically speaking, the car should start)
One more thing.. Does your DMM have an amp clamp? That could be very useful, if you have that.
Have you checked if that connection is good?
Also, have you checked your engine ground strap?
Since you have a DMM, just check and see what sort of resistance you have between:
* Battery (-) and engine block (with the (-) cable in place, of course)
* Engine block and chassis
* Battery and chassis.
Do these checks with the key off and key on engine off.
You should not see anything more than 0.1 ohms.
If you see high resistance in any of these tests, clean and re-check the grounds.
Also, set the DMM to measure draw (amps) and remove the battery (+) cable. Hook up one lead of the DMM on the battery (+) terminal, and the other lead on the (+) cable you have removed from the battery terminal.
Do this test with the key off, and key on, and post the results please.
Also, I am not very familiar with Nissans. Do they have a central circuit opening relay like Toyotas do?
You can also eliminate bad/coroded/shorted switch issues by hooking up a lead with an alligator clip on the starter solenoid. Just touch the other end of that lead on the battery (+). The engine should crank. (please remember to leave it in neutral)
Now, turn the key on, and touch that lead again on the battery (+). What happens then?
(Theoretically speaking, the car should start)
One more thing.. Does your DMM have an amp clamp? That could be very useful, if you have that.
#99
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The amp clamp is an inductive pickup. Just clamp it on ALL the wires on the (+) side of the battery and try cranking the engine normally.
Please post the results if you can do that test.
Please post the results if you can do that test.
Last edited by Godless Commie; 07-18-2012 at 11:39 AM. Reason: spelink