Heat Rave R

Sometimes it seems like even the simplest install job never quite works right the first time around... I got an Apexi turbo timer, along with the plug 'n play harness, for my '82 Turbo. After I get everything wired up, including the O2 sensor (to wire #24 on the ECU harness) and ECU ground (wire #28), I put the key into the "On" position, just to test if the timer works. Sure enough, it powers up and when I put the key back into the "Accessory" position, the timer begins counting down. However, after it finished counting down, I heard this noise come from under hood, like a pop or crack (remember, I never actually had the engine on).

After this point, I started up the engine and found that the "Charge" light on the dash is now on. Can anyone tell me what that means? I checked the underhood fuses, near the battery, and they appear intact. If something with the electrical system got damaged, how can I pinpoint what it is? And why would the timer cause it? I'm guessing it may have something to do with the timer's function of keeping the engine running after the car's turned off. I tried removing the timer harness and plugging everything back in the way it originally was, but the Charge light is still lit.

Heat Rave R

So no one really knows what kind of fault sets off the "Charge" light on the dash?

Carl's Z

Possibly one of the relays??? Haynes and the FSM have ways to ohm these out. I'll do some digging and see what I can find, also...

*UPDATE* - If you have the FSM on CD, go to EL-20. Not sure if this is the same as the hard copy or not, but it does mention some stuff about the "charge warning light"...

If you don't have it, I can email you the electrical section. Just let me know your email addy...

Carl

NismoPick

The charge light isn't connected to the ecu. It comes on when the alternator isn't putting out the right volts / amps, when the battery has probs, or when the alternator pigtale is removed / unplugged.

If you heard a "pop" then you've fried something... could be the voltage regulator, or a wire between the battery & alt. Do an alternator test & check out the wires on the alt.

Heat Rave R

Thanks for the responses guys. I suspected the alternator as well, though I haven't had a chance to go out and test it yet. However, the voltage (I have a digital voltmeter as one of my in-dash gauges) still reads normally, as in it fluctuates a bit with rpm, suggesting the alternator is still supplying power.

Unfortunately, I do not have the FSM on CD. I have a Haynes, but I didn't think it was all that great a help in this situation, unless I'm just missing it. What do you guys figure is the best way to test the alternator? At the very least, you guys don't think it's related to the ignition system right? I would've imagined the turbo timer is more directly connected to the ignition system (since it's supposed to keep the ignition running and then shut it off) than anything with the alternator/charging system.

Carl's Z

You can always go to Autozone and they'll hook ya up and do some checks for nuttin'...

PS: Let me know if you got the electrical section I sent...

Heat Rave R

Yup, I got it, thanks! Even without hooking up to anything, I can tell the alternator is still charging the battery up, at least.

So I tested the turbo timer again. If I actually start the engine, and then turn it off, the countdown and subsequent shutdown works normally and smoothly. However, once again, if I turn the key to the ON position, and then turn it back to the Acc position, without starting the engine, there's a bad noise and I think a slight judder from the engine. I gotta call up Apexi and see if they got some idea what might be happening. I wonder if any other turbo timers cause this same thing.

Purty S130

Please keep us updated.

duckyz

Well, don't DO that!!!

Heat Rave R

Haha, well I fear I will have to do it again, when I go to show it to someone who might be able to identify where the noise is coming from and what it is. .

ASA240z

heat, where did you get the harness for the timer, I thought apexi didn't make'em for the 280zx. check if the green and blue wires are swicthed, according to Apexi this could lead to a shortage, no duhh...

Anyway, I looked up for install instructions on apexi's site, there was one page that stated that some cars requires two wire to be "energized" for the car to be working properly...
http://www.apexi-usa.com/pdfWiring/9.pdf

I have an old mag with info on this intsall, it explains "where" and "what" to splice the wires. I post the details later today, after I come back from school.


Allen

Heat Rave R

The harness is actually made by Greddy. I had called up Apexi, and they were the ones who told me that Greddy's wiring/connector is the same as theirs. The timer DOES work, it just causes that weird problem when I change the key position as previously described.

Anywho, I have an UPDATE! I fixed that "Charge" warning light issue. It turned out to be one of those really stupid fixes. I had noticed that the little warning display box in the center of the dash no longer cycled through its sensors, so I was like, great, another thing that went wrong. So I checked the interior fuse box and found that the 10A gauge fuse had blown. Once I replaced it, that solved the "Charge" warning light issue! I wonder why the heck the "Charge" light would go on when it wasn't even a charging system issue!

So although the Charge warning light issue has now been solved, it still doesn't explain why the turbo timer would blow that fuse when I move the key from the "On" key position to the "Acc" position without starting the engine.

NismoPick

Have you tried the turbo timer since you replaced the fuse?

Heat Rave R

Haha, I don't have another spare 10A fuse handy, so, no, I haven't tried doing the turbo timer thing again yet.

ASA240z

So did you get the timer working? How well does the A/f reading work?

snwbrderphat540

wait.. so while the car is running on turbo timer... you turn it back to on and then to accessories as if to shut it off?

your not supposed to do that... there should be an engine terminate button on the turbo timer itself... thats what you use.

Heat Rave R

Ok, so I tried reconnecting it again this weekend. The timer does indeed function in that it'll count down the car and give me an estimated A/F reading which I actually found useful. However, it's still consistently blowing my gauge cluster fuse as soon as I turn on the car. I guess that's the biggest mystery about it.

snwborder: no, I was saying that I turn the key to the "On" position but do NOT start the car, and then I turn it back to the "Acc" position. That's when it does that odd engine jerk/noise. I guess it's trying to fire up the car cuz it thinks the engine was actually on.