Lesabre died /shut down while driving,turn key to start makes no noice,have no voltage to purple wire,checked starter, and relay,and neutral safety,fuses all good

Do you know what a wiring diagram is ? How to use a DMM - digital multi-meter to diagnose automotive electrical circuit's ? Looking at a wiring diagram to see what all is involved in the starter circuit , main battery cables , park neutral safety switch , starter relay etc.. Find video's on youtube . Do you have a manual or automatic trans. ? The purple wire get's B+ voltage from the starter relay in the underhood fuse / relay box .

How to voltage drop test starter motor circuit
When your car wont crank or start part 3 How to check relays fuses...

Without more information regarding make model and year that's a tough one to answer.Most vehicles lately use a starter relay so there is no wire that goes directly from the ignition switch to the starter,it would go from ignition switch to a neutral safety switch then perhaps a anti theft device then to the starter relay,then the starting wire would travel from the starter relay to starter.In older gm products the common ignition to starter wire was purple for years.

Check for power on the small purple wire when the key is held in start. If the purple wire has power, then the problem is your starter or the starter solenoid mounted on it. That is, if all your battery cable connections are clean and tight, and battery is fully charged.

If the small purple wire has no voltage with key in start, problem is between the key switch and there at the starter solenoid. Test your transaxle selector switch, the park/ neutral switch. There is also a relay in the circuit, called the starter interrupt relay. But if you have a Theft Deterrent system, you will need to check that.

I think the purple wire (or maybe the yellow) from the neutral safety switch goes to the coil side of the starter relay, turning it on so power is sent from there to the starter solenoid. You could check for this signal to the relay with a test light. The key must be held in start while you probe the other two terminals for the relay. If the signal is there, either a bad relay or the coil side of relay is not grounded properly. It is possible that the coil side ground is the neutral safety switch-grounding the relay's coil side only in park or neutral-in which case the nagging light on shifter (between off and run, it only works?) may be telling you the safety switch is the problem.

You may need to look at a wiring diagram, Greg. But the starter relay is the last component in the start circuit before the starter solenoid. From battery to ignition switch to "crank" fuse to neutral safety switch to starter relay to starter solenoid to starter-and back to battery through ground. That is the start circuit. Just that the wiring tying them all together makes it complicated.

1. Make sure your battery is fully charged.
2. Check connections from battery to starter relay.
3. Make sure you have voltage going to the start side (small wire) of the relay with the key in the "start" position.
4. If you don't have voltage going to the start side of the relay (small wire) with key in the start positon, then your starter switch is faulty (under dash usually mounted on top of steering column).
5. If you have voltage to the start side of the relay (small wire) with key in start position, and it don't click when trying to start your car, then the starter relay is bad.
6. If your starter relay clicks, but engine don't turn over, then the starter is faulty.

Be sure the AIR BAG/VATS fuse 10 amp, is good. there is a STARTER ENABLE RELAY up high on the left of the steering column. I ASSUME the anti theft light is not flashing?" at the STARTER ENABLE RELAY the YELLOW wire is hot in the crank mode and comes out large PURPLE to the starter. the small purple wire is hot in the crank mode if the fuse (air bag/vats) is good. the small yellow is grounded through the park switch and the VATS module (anti theft)

Starter enable relay is under the hood in a fuse box that runs along the bottom of the windshield wipers, there are (2) twist knobs and (1) wing nut in the far left hand corner of the fuse box cover. remove cover. now you will see a group of smaller fuse box remove covers and look inside there will be I.D. to tell you which is which.

Looking at the end of the solenoid on top of the starter, the battery cable hooks to the larger stud on the top "12 o'clock". A smaller purple wire connects to the smaller terminal at 3 o'clock and the stud at 6 o'clock connects to the flat wire coming out of the starter. The purple wire comes from the neutral/park safety switch, which is fed by a yellow wire coming from the start relay which is fed by a yellow wire coming from the ignition. The start relay is also controlled by the Pass Key decoder module. Hope this helps, as for starters.
Check the fuel pump relay

The fuel pump relay is located to the right of the glove box.

Remove three 8mm screws (along the front edge) and a wingnut (drivers side near the accelerator) to loosen the insulation panel. Twist out the light courtesy light and using a pair of pliers squeeze the plastic nipple to remove the SIR. Remove the insulation panel from the vehicle.

After the insulation panel is removed, the fuse/relay panel will be to the right of the glove box. The insulation panel should have a diagram of the fuse/relay panel layout.

The relay should be in the left column of relays just above the fuses.

A Good contortionist with small hands and this can be done in about 15 mins.

What I would check first is the starter, when it don't wont to start, with a test light check voltage down at starter, the small wire on the starter come's from the ignition switch, while some one holds the key to start check voltage at small wire, there should be voltage there as long as key is held on start, on the big wire at starter it should always have voltage with key on or off, if you do have voltage replace starter intermitly going out, now if you don't have voltage at small wire, check or replace neutral safety switch.

The starter is malfunction at this time. it could also be a ignition issue as well. here is a quick starter test procedure that will help you troubleshoot a bit.

Step 1
Check for 12 volts on the large wire attached to the top terminal on the starter relay. It should have battery voltage. If not, the battery, terminals or wire is bad.


Step 2
Check the small wire on the solenoid for power when the key is in the start position. Remove the small wire on the solenoid and have a helper hold the key in the start position. Check the wire for battery voltage. If there is voltage, the starter is bad. If there is no voltage, replace the wire.


Step 3
Check the fuse in the fuse box under the hood on the left fender well. If it is good, check the relay by pulling it out and checking for power at one terminal with the key off. If there is no power, the problem is in the fuse box between the fuse and the relay. If there is power, have the helper hold the key in the start position once again and check for power at another terminal from the ignition key. If there is power, the relay is bad. If there is no power, the starter circuit is suspect.


Step 4
Check to see if there is power to the neutral safety switch if there is no power at the relay. Use the voltmeter to check for power with the key in start. If there is power going in, check for power going out. If there is no power going in, the security system or ignition switch is suspect. If there is power going in and none coming out, the switch is bad. If there is power coming out, the problem is between the neutral switch and the relay.


Step 5
Remove the cover on the bottom of the steering column. Check the solid yellow wire for power when the key is in the start position. If there is no power, the ignition switch is bad.

ok. the relay is under dash drivers side left of the steering column. now first check for power with key in the start position. at the heavy yellow wire at the relay and then check the purple wire if both have power then your neutral safety switch mybe at fault. check it as well. check for power at the switch bolted to transmission. the two heavy wires going to the switch will be starter in and starter out. so check for power at the two there if power goes in but nothing comes out the change the neutral safety switch.