No need to mess with the radio. Just unbolt the Tell Tale Display.
Looks like the Starter Enable Relay is behind that panel.

I don't see any connector with wires like that in the manual. May be someone will respond.

 

Is that the red GM factory manual??? ST-364-86???

I have that...worst manual I've ever read...I can't find any of what I want in it...No index, no TOC...

 

That manual is the Bible for your 86.

The manual has a chart telling you what voltages
should be at the Starter Enable Relay.

Have you gained access to the Starter Enable Relay?

 

I'll look for it this week...With no page numbers, it's hard to find anything...

There's a chart at 6D-3, but no starter enable relay...

Looking for the Multi Use Center disassembly section now...I'll find it, eventually...

 

Start at the bottom right side of Section 8A 30-4

 

Got the drivers seat out, and the plastic panel under the ECU...

I'll try for the DIC panel next...

Reading 8A 30-4...I've already done up to 3...I don't know where Ignition Switch connector C2, Terminal S is...

...But it's probably...behind the multi-use center...

 

Here's a picture of the Tell tale display. To remove it you remove the headlight ****, 3 screws on the end of the dash and some screws in front of the dash cluster. Once that bezel is loose remove the screws for the center dash bezel. That's the bezel surrounding the radio.

Why did you remove the driver seat and the plastic panel under the
ECU The ECU is under the passenger side of the dash.

Do the test measurements at the Starter Enable relay.

 

Gotcha...

Pulled the seat out because at 6' and 210# I don't fit in the footwell with the seat in. Now I can lay on my back and look up into the dash easily.

I pulled the kick panel off the pass side to see what the light connector looked like...It's a pink wire with a wht stripe, and an all wht wire in a stacked connector...the same as my loose connector on the drivers side. My 86 never had a drivers side kick panel (I suppose it's on a shelf in the PO's garage) so I never missed the light.

One mystery solved.

The relays behind that telltale panel are next.

Thanks for the pic!

 

OK, I finally got up enough courage to tear into the driver information console...



First thing I checked was the two fuses...Top one is 15 amp labeled "Theft", bottom is 5 amp labeled "Cinj"...Both show continuity...

I visually checked what I think is the starter enable relay (the one in the middle that I labeled "2"...the one I labeled "1" should be the horn relay per the manual, and "3" should be the "audio alarm module"???)...

Step 3 says to check ignition switch connector C2, terminal S...I have no idea where those are...so I'll skip to -

Step 4 says to remove starter enable relay and connect a voltmeter from terminal E of connector and ground...and turn ignition switch to START w/clutch pedal depressed...(I assume this requires battery hooked up again)...So, I pull the relay out...

Removing the relay presents a sickening sight...brown slimey crap on all the connectors, on both the relay itself and the harness connector...







I'm guessing this is a burned out relay...No other connector has this crap on the terminals...

Before I try connecting the battery & voltmeter, I'm going to clean that harness connector...CRC makes a "QD Electronic Cleaner" in a spray can; I stuck a rag around the connector and sprayed away...Cleaned it up very nicely...

 

I saw that brown colored goo on a 87 that was having a problem with the cooling fan relay. I thought someone had packed the relay connector socket with the goo. Cleaned that goo out of the connector plug and the relay started working.

Seeing your picture of the relay connector it must have come from the factory like that.

With the relay removed, you should measure 12 volts to ground on the Yellow wire on Pin E and also Pin C when the ignition switch is in the Start position.

With the relay installed, every time you turn the ignition key to Start, you should hear the Starter Enable relay click.

That would indicate the relay is enabled and the Vats Decoder Module is grounding the Dark Green wire.

If that happens you should measure 12 volts coming out of the Relay on the Dark Green/White wire which goes to the Clutch Safety switch and after that switch turns into the Purple wire at the Starter Solenoid.

 

If that were so, then why don't all the connectors have that goo???

I do have battery voltage to pin E with relay out and ign switch to Start...

The next item in the manual's checklist [item # 5] is to connect a jumper from E to A of the starter enable relay connector and see if engine cranks when ign is switched to Start...So, I put the starter back in, and tomorrow I'll bolt up the front exhaust pipe and try jumping A to E and cranking it over...

 

Do you think Bubba put that brown goo in the connector?

Bubba must have been a brave guy to go through all the trouble
and remove the DIC to put the goo in the plug.

Jumping E to A bypasses the relay.

You all ready know it's not the Clutch Safety switch so why don't you
install the relay and see if it clicks?

Maybe cleaning the goo out solved the problem.

If the Relay doesn't engage check the Dark Green wire for a ground signal.

You don't need to install the exhaust for the starter to work.

 

No...I think it's electrical goo from inside the relay...I've seen other fried electrical components that also leaked crap like that...

Yep...It's step # 5 in the manual...

BTW: One of our members has a site describing bypassing the VATS module/relay/switch -

http://www.joestradingpost.com/vats/

I'm going through the manuals diagnostic items...Someone suggested I try that...

When I cranked it over two weeks ago, it started before it even made one engine revolution...I don't want hot exhaust gases blowing on my nice clean starter & O2 wires...

 

Got the front exhaust pipe connected; jumpered A to E on the Starter Enable Relay connector (bypassing the relay), and turned ignition switch to Start w/clutch depressed...Starter engages; engine cranks...

This was Item # 5 of the manual's diagnostics...

...If engine cranks, go to Item # 6

Item # 6 is to remove the jumper, reconnect relay, and ground the DK GRN wire at pin B of the Starter Enable Relay, and turn ign switch to Start...

I don't see how I can ground the wire with the relay installed...

 

You can strip some of the insulation off of the Dark Green wire. Or use a sewing needle and pierce the insulation. Use a jumper wire and ground the sewing needle.

You could also pop the cover off the relay and jumper pin B to ground.

 

I ordered a new Starter Enable Relay from Advance Auto and plugged that in and tried it...no good...still no crank...

Back when I jumpered the A to E contacts in the Starter Enable Relay harness connector, the engine cranked & started, but there was/is no sound from the fuel pump, and the engine died after 4 - 5 secs...

I'm pretty much out of options now...I don't have the special diagnostic tools for the rest of the tests described in the manual...

Having it flat towed to a dealer (or Corvette specialist) looks like my last resort...

As you may have noticed, I'm pretty much bummed out by all this...I used to enjoy working on cars; but now, when I look at this car, I'm just really depressed...

 

If you would have grounded the Dark Green wire and the engine cranked that would have indicated the relay was good.

The reason why the engine only ran for a couple of seconds is because the ECM was not pulsing the injectors. Jumping A to E only verified the 12 volts from the ignition switch circuit was getting to the starter solenoid.

When you first turn the ignition switch to On, the ECM will enable the fuel pump for about 2 seconds. It will shut the pump off If there are no reference pulses from the distributor indicating the engine is not be cranked or running.

That's normal. Obviously there must be some fuel pressure in the fuel rail or the engine wouldn't have run for the few seconds it did.

Also if you cycle the ignition switch On and Off a couple of times and not wait a couple of seconds, sometimes the ECM does not enable the fuel pump.

Your no crank problem points to the Pass Key Decoder circuit.
Either the key pellet is not being read properly because of bad contacts in the ignition key lock assembly, worn key pellet or the Pass Key Decoder Module is bad. (Not likely). If you're using a bypass resistor, it may be out of tolerance.

1) Are you sure when you turn the ignition key On, the Security light bulb comes on for a second then goes out?

2) What happens when you have either door open. Does the Security light flash on and off?

3) What happens with the passenger side door closed and the driver side door open and you lock the doors with the power door lock switch.

Does the Security light stay on solid?
Unlock the doors using the power door lock switch.
Does the Security light start blinking?

 

Thanks for sticking with me here! This is very frustrating...

At this point in time, the Security light does not come on at all (both doors closed, switch to Run)...

Yes; Security light flashes...

Yes

Yes

Drivers power door lock switch seems awfully loose...Like the plastic thingy isn't captive like it should be...but it still works...

 

No; all original key/lock cylinder...No bypass (that I'm aware of)...

My apologies about the Security light...I've been doing all my testing/bypassing with the drivers door open...

 

Some more - If I leave the drivers door open, Security light flashes...If I then turn ign to Run, it goes out immediately...if I turn it all the way to Start, the Security light starts flashing again...(door open throughout)...