HI-6 not recieving trigger signal from Unilite

[fiveleaf]

Was hoping the car was going to run today. Just put the new starter motor in, and turns over well.

The HI-6 has a signal light on the front of it, which is solid red when powered up, and flashing red while cranking to let the user know that it is receiving a valid trigger signal.

Mine turns on to solid red, but does not flash when cranking. In the troubleshooting manual, this means I am not receiving a valid trigger signal from the distributor.

The wires to the distributor have all been checked for continuity all the way to inside the distributor from the HI-6.

I tested the HI-6 by taking the white trigger wire and touching it to ground. It flashes the LED every time it is released from ground, as it should.

Wiring the Crane HI-6 to a Mallory Unilite distributor is shown clearly in the HI-6 manual. http://cranecams.com/pdf/90006000e.pdf

Basic wiring for the HI-6 is shown on page 2.

Green Tach output taped up for now, blue cylinder select grounded (6cyl engine selected).

Recently rebuilt L28 (<200mi)

Mallory unilite distributor (Tested 3mo ago, new ignition module 3mo ago).

Crane HI-6 ignition

Crane PS-92 coil

Edited June 4, 2010 by fiveleaf
Take out sig

[fiveleaf]

My next move would be to take the distributor off/apart to look for bad connections, but was wondering if there should be something else to check first.

I've been repairing the 240's engine bar harness for the last few weeks and may have pulled something loose putting the new 3-prong quick-disconnect on the unilite.

I also have a used ignition module for the unilite at the shop, but I'm pretty sure that they are magnetic and don't usually just stop working.

Any ideas in which direction to go?

[Zed Head]

Doesn't the coil ground through the tachometer circuit?

Just a guess, no real knowledge of what you're doing. But I did see that you have the tachomoter output disconnected, although I'm not sure what effect that would have with your setup..

[alhbln]

The unilite distributor has an optical switch but acts like a points or transistor setup to the outside. The green wire supplies the ground signal for the coil, so for triggering the Hi-6 you connect the green wire of the Unilite distributor to the white wire (points input) of the Hi-6 unit (which you probably did already).

It appears that either the Unilite distributor is not getting +12 volt via the red wire and ground via the brown wire, or the Unilite module in the distributor is defective.

While the ignition is switched on, measure the red against the brown wire with a multimeter to make sure that the Unilite receives power (+12V). If this turns out ok, connect a small bulb (4 or 21 watt standard car bulb) or a test light to battery (+) or red and the green wire. It should flash when you turn the distributor or try to start the car.

You should also be able to trigger an ignition by introducing a piece of cardboard inside the optical switch, when removing the cardboard you should get a spark from the Hi-6.

[fiveleaf]

Forgive my inexperience.

----

Green (+12v) from the Unilite get's +12v from a section of the fuel pump +12v. If the fuel pump is on, I know it's getting power.

Brown (ground) from the Unilite is grounded about a foot away.

Green (trigger out) from the unilite is to the white (points) into the HI-6. Tested for continuity from it's connection inside the unilite to the other side of the firewall (bullet connection to HI-6)

-----

Seems weird that it would be a defective module. I have an extra, but isn't it magnetic and more subject to wear (opposed to failure?).

1) I'm quite certain the Unilite +12V (red) to earth (brown) is good. I'll test it anyways.

2) Connect one end of the test bulb straight to Batt (+).

Connect the other end to both the red and green wires at the same time.

Turn the engine over. Blub should flash with trigger output.

Isin't this what the HI-6 flashing indicator LED supposed to show?

3) With the ignition on "Run", is to block/unblock the optical trigger. I should get a spark from the main coil wire.

Measured with a timing light or spark to earth.

Just wanted to clarify #2 before proceeding.

Edited June 4, 2010 by fiveleaf

[alhbln]

Tommy,

quick question, are you sure that the Unilite gets +12V via the green wire or just a typo? Should be the red wire as in 1).

You said that your extra module is not magnetic, but the one installed in your Unilite should be optical. Could you send both parts number so i can look up these?

The test in 2) puts a load on the Unilite output to check if the output if functional and goes to ground, its a simple test to check the basic functionality.The green wire goes to one terminal of the bulb or test light, the red wire to the other terminal.

Good luck,

Adrian

[Zs-ondabrain]

Unilites for the Datsun 240Z DO NOT GET 12 volts!!

They are designed to run on about 10 volts via the ballast resistor. 9.5 volts DC is optimal. So make sure your ballast resistor is up to par. If it's not, you'll blow the module.

And at about $80 a pop, it can be a pricey mistake.

Dave

[fiveleaf]

I'll grab the part numbers next time I go up to base. It's parked outside, with the interior down to bare metal. I was trying to get it to run for a lapping day, and ended up stranded in a parking lot.

I leave for a week-long exercise (military) on Monday, and if I can't get it running tomorrow, I will flat-bed her to somewhere.

I believe both of the ignition modules are the same. It was another regular at the auto shop on base that told me it was a magnet that wears out after I told him it was hall effect. I didn't know enough about the module to contradict him.

Adrian, yes, you are right; the red wire is receiving the +12V currently. I'll try the test tomorrow morning.

Dave, is this supposed to be +9.5V on both START and RUN?

It is currently wired inline with the fuel pump, for testing purposes. I'll head to the local parts shop and take an extra ballast resistor.

Would the module blow immediately? If so, It's blown, and you just saved me from blowing my spare.

My next step is to pick up a spare ballast resistor, install it with the test wire (from the fuel pump), and try the previously mentioned tests. If they fail, I'll install the new module and re-test.

As of Monday morning I'm gone on ex for 7 days, but will continue next Monday if I don't figure this out tomorrow.

[Zs-ondabrain]

The Unilite is supposed to run the same as a points distributor. So however a stock dizzy works.... That's the way the Unilite was designed. As a drop in replacement. Ground the brown wire, and the green is the trigger wire (to the Neg on the coil) can't remember where the red goes off the top of my head.

It can take hours to weeks to blow the module, but it will fail if 12 volts is fed too long.

I only know this because a friend blew his after 2 weeks without a ballast resistor. He didn't drive it much so there's no telling how long it really took.

Dave

[alhbln]

Good info, thanks! I wonder why Mallory did not care to add an LM7810 then, car components should be able to handle 12-16 volts without any negative effects.

Magnets don't usually wear out (if you dont cook them or hit them with a hammer) but the pickup could fail, both issues are not very likely with a new module though.

[alhbln]

Did a quick research, you seem to use a Mallory #609 type ignition module with a VR magnetic pickup (if you have a star shaped trigger ring, it is usually VR, a pot style trigger with rectangular gaps indicates a hall pickup).

The Unilite documentation is not very clear about this setup, it recommends that you should use a ballast resistor between +12V and the ignition coil (+) to restrict the maximum current which could destroy the module. But since you are not driving a coil with the Unilite module but merely trigger an external ignition system (HI-6), this should not be an issue. In the Mallory wiring sheet, the red wire of the module is indeed directly wired to +12V.

This is the excerpt from the Unilite magnetic pickup module installation manual:

http://www.malloryperformance.com/pdf/609.pdf

(Figure 4, Page 2) NOTE: The purpose of an ignition ballast resistor between the ignition switch (12V) and the ignition coil positive terminal is to restrict current flow through the ignition coil. Failure to use an ignition ballast resistor will eventually destroy the Ignition Module.

From that perspective i would say that it is safe to run the Unilite module with a +12V feed if you only use it to trigger a HI-6 or MSD 6A CD unit. The Mallory Hyfire 6A (identical setup to a Hi-6 unit) also shows a direct wiring without ballast resistor, have a look at the wiring sheet on the bottom of page 6:

http://www.malloryperformance.com/pdf/6852M_6853M.pdf

Dave, what do you think?

[fiveleaf]

I left the paper with the distributor numbers with the car, before I left for the field.

Visually, it's rectangular holes with an optical device. I'm not an expert, but I think it's safe to assume it's Hall effect.

I agree with Adrian; I'm opting out of the resistor and going to remove it from the harness entirely.

I didn't want to test it before I left, out of fear of damaging the module without a resistor. I just got back in, and will try this all tomorrow.

For now, I'll go enjoy a thimble of beer and pass out. I'll keep you updated, thanks.

EDIT: Work has been unexpectedly fast-paced all day for the last few days, and I haven't had a chance to get to the 240. It needs to run by Friday. I'm sure it will, and that my issue is probably just the unilite module.

Edited June 15, 2010 by fiveleaf