Mallory Hyfire 685 starting issues
Mallory Hyfire 685 starting issues I recently added a used hyfire 685 box to go along with my nitrous install. The box gets power and the car has started once with it installed. I was able to check that it was functioning (tested rev limiter) and found that it was. It only started after a lot of cranking. Now, it won't start at all with it wired in, but when I go and switch back to stock (using the MSD harness) it starts right up. I can't seem to find a contact number on Mallory's site, and their knowledge database is a little rough. What should I test?
start retard is set to .1, which is the lowest it will go. The window switch low and high are set to 3500 and 5700, respectfully. The rev limiter is set high enough as well. I'm stumped. I just went out and ran a wire from the battery to the 12v keyed power on the hyfire to test if it was getting a strong enough signal, and it made no difference. Still no starting when it is plugged in.
Did you wire it correctly? You basically are going to hook up a total of 6 wires to get the box to function, one is for power, one is for ground, and the other 4 will be crimped to the MSD harness which will in turn plug into your ignition coil. Here is the correct color coordination for the MSD harness to the Mallory box:
Red to Red
Black to Black
White to Green
Orange to Yellow
I'll go check the settings on my 685 right now and post up ALL the settings.
Red to Red
Black to Black
White to Green
Orange to Yellow
I'll go check the settings on my 685 right now and post up ALL the settings.
Understand that you won't use all these settings but this is what I use on my nitrous LT1:
1) 6.5
2) 2.8
3) 4.0
4) 0.1
5) 3.0
6) 5.8
7) 0.5
8) 0.1
9) 8c
A) 3b
If it doesn't work after this let me know. You probably have "Tach Test" on and it won't start this way either. Let me know and I'll tell you how to turn it off.
1) 6.5
2) 2.8
3) 4.0
4) 0.1
5) 3.0
6) 5.8
7) 0.5
8) 0.1
9) 8c
A) 3b
If it doesn't work after this let me know. You probably have "Tach Test" on and it won't start this way either. Let me know and I'll tell you how to turn it off.
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My settings are similar enough to not cause anything odd And I am pretty sure I made sure to turn off the test tach by following the instructions in mallory's pdf. I switched it to mode 1, turned it off, then back on. no luck though.
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Verdad Gallardo Could be a bad box as mentioned. Thats the only other thing I can see being wrong at this point. I just know people forget about the tach test thing, I know I did the first time and I couldn't figure out why it wouldn't start for a while. LOL Just make sure it is off for sure. As you said turn the key to "accessory", 685 to option 1, key off, then back on.
Mine fried after a year i got summit to exchange it for free under the one year warranty. I was cruising along the highway to my mercedes benz job interview when i looked down at the speedo and said out loud this car runs real good its so dependable. Not 2 seconds later it died. How ironic was that. I bypassed the box and it stated right back up.
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I figured out my issue. I was running a keyed 12v to the mallory when it should have been a constant from the battery. I ran a short wire from the battery straight to the mallory and the car fired right up. The window switch, rev limiter, and timing retard are all working just fine. Thanks for the help guys.
