Indigo digital ignition troubleshooting

[funkyculley]

Engine isn’t turning over, have power at coil but the LED light on the indigo unit isn’t lighting up when I hit ignition .

Are there any common troubleshooting tips? I read the only reported failures were due to lightning but I’m not getting any response from the unit

[Dave Neptune]

It has been a long time since I read through the Indigo Booklet. I do not remember the trouble shooting chart. However logic to me and my poor memory leads me to think that the LED indicator lit when the signal to the coil to fire was sent to the coil this lit the LED. This was only to indicate that the coil was firing not necessarily that the system was working.

The photo optic sensor in the distributor fired when the rotor window opens and the sensor sees the light. A very simple electronic switch that replaces the points.

Check carefully all if the wires connecting the Indigo unit and under the cap for breakage or worn insulation to be sure of the connections and integrity of the wires. The cap pinching a wire in the slot that they go through under the cap should be inspected very carefully because most problems occur in that slot. Once assured check the coil itself.

To check the coil itself, remove the wires from the negative side of the coil. Then remove the coil lead to the center of the distributor cap and fasten it to the block or a ground with the gap from the center wire about 1/4 inch from the block. Then when power is supplied to the positive side use a piece of wire to ground the negative side of the coil and you should see a spark if the coil is good.

You could also call Tom at Indigo and he may be able to send you a trouble shooting schedule.

Dave Neptune

[joe_db]

Tom can explain a simple test to determine if it was the module or the sensor. When mine croaked it was the module, I had to get another one.

[funkyculley]

Perhaps starter, not ignition system?

I posted the other day when my engine wouldn’t start; I immediately assumed it was due to the indigo ignition system I had installed, but after further research and speaking to Tom from indigo, I no longer believe the system to the culprit.

After some research on the forum I’m fairly certain it is the starter. When I push the ignition I hear a clicking sound from around the solenoid/starter. I disassembled the solenoid to clear corrosion inside and at points of contact, now I get a more aggressive clicking but still no crank.

I’ve tried to short the solenoid externally with a screwdriver, per a suggestion I read a few times here, to no avail.

Is it worth disassembling the starter and cleaning it? Have people had luck doing so with the a4 starter? Ideally I’d like to just get a rebuilt unit from Moyer but I’m currently on anchor in the Bahamas would like to be mobile while I wait on forwarding services/international shipping.

Thanks a ton in advance & please pardon my ignorance

[Dave Neptune]

If you are getting power across the solenoid by crossing the 2 large posts with screwdrivers or such and no joy then the brushes are not contacting the commentator of the starter. Could be bad brushes or a dirty corroded commentator. This is not an uncommon way for a starter to fail.

Has the starter been slowly over time turning the engine slower and/or taking a few twists of the key to get it to start? If so it is probably power not getting to the commentator from the brushes. They can often be cleaned and in some instances spraying the inside with contact spray will yield a temporary remedy, not a fix.

Has the starter recently been flooded or gotten wet?

The LED not blinking led me to the Indigo unit and not the engine not being spun, sorry.

Dave Neptune

[funkyculley]

Thanks for your reply, Dave!

It had been taking more twists to get the engine going as of late and may have gotten wet on a recent rainy passage with trips in/out of the cabin.

I’ll take take off the starter then and try to clean it, will report back

No worries on indigo, my post could have definitely led you to that conclusion

[hanleyclifford]

Wouldn't hurt to do a load test on your battery. Also check batt ground connection.

[funkyculley]

Those were my first thoughts, but batteries look all good

[Al Schober]

The springs that hold the brushes against the commutator are carbon steel and will corrode - faster if the starter has had a dose of bilge water in the past. If you have access, you can pull the cover and have a peek. Removing the starter isn't that big a deal.
I'm tempted to offer to come give you a hand...

[joe_db]

Triple-check the wiring. What is the voltage at the starter when starting and what is it not starting?
What is the voltage drop between one of the bolts holding the starter on and the negative battery terminal when cranking?
Try taking the starter off and forcing it to rotate a bit. Sometimes they get a bad spot and won't start if you land on it, but will work somewhere else.

[funkyculley]

Try taking the starter off and forcing it to rotate a bit. Sometimes they get a bad spot and won't start if you land on it, but will work somewhere else.

Should the wheel turn freely? How much pressure should I expect to put on it? It turns when I raise and lower it but not while stationary on the interior rod

[Dave Neptune]

The gear should turn freely in one direction and not the other as it rotates on the shaft. Not sure as to what type you have of the 2 most common.

A "Bendix" style uses a twisting groove (thread) to force the gear forward to engage the starter ring. If you rotate it it will slide freely in one direction and resist by turning the armature for a possible better contact area in the other direction.

The other uses the solenoid via a set of jaws to force the gear forward into the starter gear when engaged and will freewheel for disengagement once started in one direction.

Try rotating the gear while looking at the shaft one way is free spinning and the other is against the shaft causing the shaft to rotate which is what you seek.

The rotation of the shaft may put the brushes against the commentator in a position where the electricity will flow. If this works you will know that the problem is in the contact area between the brushes and the commentator. Sometimes it can be cleaned and work for a while however it is indicative of corrosion which needs to be addressed by a rebuild.

Dave Neptune