ok i went down to the dealership today and spoke with my service manager

and he pulled over my tech guy .. the one who works on corvettes all day .. etc etc

and we spoke for a minute and he said that most likely my car didnt have a relay put on it .. something about not all cars were accepting it

.. ok if thats true .. why the heck do i have my starting issues .. i told him i went through and checked all the grounds .. he then asked me about the grounds inside the car (anybody know which ones that are btw) .. and i said no .. i didnt really know there were

i get the click from the BCM area (i assume the anti-theft relay) on every turn .. i have full voltage .. he said something about it goes searching for the voltage (which i recall reading) if it doesnt turn over immediately .. but i thought the final recall included removing the column lock and installing a realy to statisfy the pcm .. ??? im a little baffled to say the least.


any thoughts ..

 

If the ignition switch, clutch switch, or BCM were inhibiting the start, the theft deterrant relay would not be clicking. The fact it is clicking, is a good sign, you've eliminated a lot of possibilities.

If your theft deterrant relay is clicking, but the starter is not turning over...I can almost bet it's the starter itself failing, or possibly the relay itself is bad.

Mine acted the same way intermittently for a couple weeks before the starter quit permanently.

You need to get at that relay with a meter, and check voltages during an attempted, but failed start, to nail down the source of the problem, no other way about it.

 

The column lock system has nothing to do with starting the car. It only cuts fuel if you try to drive the car above 3 MPH with the column locked (or if the BCM thinks it's locked).

From memory, the car needs the following for it to start:

- The Pass Key system properly reads the resistor pellet value on the key.
- The Ignition cylinder has a switch in it that that must be closed (i.e. the key is in the ignition).
- The Clutch must be fully depressed (MN6) or the A4 must be in Park or Neutral. There are switches for these. The clutch switch behind the clutch pedal, and the A4 switch is inside the center console.

Have them check the ignition switch and the clutch (or A4) switch. My guess is if they messed with the column lock area during the recall, they may have loosened the ignition switch connector.

 

i already checked (replaced) the clutch switch .. so that's out of the equation ..


could somebody lead me through checking the voltage .. i've got a voltsmeter but not really sure how to use it properly .. if i've got two like on a house switch, no probs .. this well .. im not exactly sure ..

 

i really think it's an elec / voltage problem .. it showed up only after the column lock recall was done and it's been doing this since beginning of april .. i've been ruling htings out left right and center .. but when i heard of the column lock recall relays going bad, it just seemed like that could be the problem ... i'm wondering if maybe they nicked a wire or something .. because it doesnt always do it .. it comes and goes .. and if i hold the key down sometimes for ~ 30 seconds as it clicks 2-3 times .. it'll turn over.

 

To test the TD relay and at least isolate where the problem may be.

First, find a good ground point near the BCM. (I forget, but if I recall the BCM housing is not grounded). Attach the black lead of the meter to this ground point.

Set your meter to read volts DC.

You will probably need an assistant to do this, as you'll need to test with the clutch pedal pressed, and the key turned to start. Note, if the car starts, testing is pointless, since obviously everything worked. You can really only test when it's not working, and yes, this can be frustrating.
On the relay, there are 4 wires...red, yellow, yellow/black, and purple.

The red wire should have 12v all the time, it comes directly from the battery, and runs through a 60a fuse in the interior fusebox.

The yellow wire is what comes from the ignition switch, through the clutch switch. It should read +12v during an attampted start.

The yellow/black wire comes from the BCM. During an attempted start, The BCM grounds this wire, which combined with the +12v on the yellow wire, actuates the relay.

The Purple wire is what runs directly to your starter solenoid. During an attempted start, when the relay actuates, this purple wire should have +12v. If it does, and your starter isn't working, it's a pretty safe bet your starter is bad.

Never rule out coincidence. If your TD relay is clicking when trying to start, that means all the interior wiring and switches is good. The problem has to be downstream of the relay, and fortunately, there isn't much left to check at that point. The fact you say the relay is clicking is a very important discovery.

It is possible like you say it's something else, like wiring around the column area, but if that were the case, the TD relay would not energize!


Here is the location of the theft-deterrant relay (circled in yellow), directly above the BCM:



And a closeup of the relay:


You are actually seeing the base of the relay from this angle. The relay itself is on the backside of that black connector.

Also, here is the schematic of the starting circuit:




Hope that helps some...

 

thanks. .. i'll give this a try .. maybe when i tried replacing the relay i replaced the wrong one .. it's odd that it's on-and-off ..

do you know where the yellow/black wire is grounded? .. is it possible for that ground to be bad? ..

i appreciate the help .. looks like i'll need a helper .. hopefully the dang thing will start doing it again .. i tried going out there a few minutes ago .. and guess what .. starting no problems .. as it did when i left the dealership .. ...

darn gemlins.


thanks.

 

i was just thinking and remember reading about how headers are notorious for killing starters .. should i rule this out? or consider it a possability?

 

That wire becomes grounded internal to the BCM. This is why and how it's part of the theft system. If the security system is compromised, the BCM won't ground that wire, and the car won't start, even if there's 12v from the yellow ignition wire.

If you lost the BCM grounding, you'd definitely have a whole mess of other stuff not working.

If you even suspect this...you can easily run a jumper wire from the yellow/black wire on the relay connector to a true ground point, that would definitely eliminate the BCM grounding as a possibility.

But note for all you who suddenly realized how to easily hotwire the car , if the BCM was truly inhibiting the start for whatever reason, and you jumpered that ground wire, although the car will crank, I'd be willing to bet the "pull key" msg will appear and car will shut down if moved.

 

Not to be overly-simplistic...but have you had the battery tested? If you have a bad cell it could be unloading under a load (starting). This could cause the various relays to act up during starts. This would not show up on a simple voltage test. Have it load-tested.

 

.. thank you anyways.

 

ARRHG .. im checking it and im getting 12volts on start up ... but the car turns over .. it did it once this morning .. now it wont do it again ..

are there grounds inside the car? i was going to try and check those ..

 

WAAWHOOO .. i never thought i'd be so excited for it not to start.

when it doesnt start the purple wire has no voltage .. after holding the key for a few seconds, it gets voltage.

i think it might be another relay that is clicking or another part inside the bcm .. becuase it i have heard a series of clicks and one when i stick the key in another when i attempt to turn it ..


i'm going to go try the yellow wire now and see if its getting voltage at start up .. and if it is .. i'll go get a new relay and be done with it.

 

no voltage coming from the yellow wire on the non-starts.

.. time to tear further into the car ..

 

If that's the case it's looking like the ignition switch, or a loose connection there. (just as you suspected, something they may have disturbed in doing the CL work). Specifically, at the ignition switch, the red wire from the fusebox feeds 12v to the ign switch, and when you turn to the start position, you energize the yellow wire. The yellow wire runs to the fusebox, through fuse #14, then is a purple wire that runs to the clutch switch, and when the the clutch pedal is depressed, closes a contact and then energizes the yellow wire...which then runs straight to the TD relay.

Since the clutch switch is also in-line on that wire's path to the relay, although you may have recently replaced it, it's easy to recheck for correct operation.

Also, check the #14 fuse in the inside fusebox, it's 10a and labeled "crk". The fuse will be good, just make sure it's fully inserted and not loose.

 

i'll go ahead and check that fuse .. but i closed the circuit on the clutch switch .. i just jumped it.

i've got the interior all apart and unless there is a loose or crimpted wire inside the steering column (piece only accessable by removing the steering wheel) .. i dont see any underneth the dash .. i'm also now testing at the ignition switch itself .. i've got the MM grounded at the left inner grounding point and attached the other side to the yellow wire off the switch itself .. now i'm just waiting for the car to do it again everytime i go to start it up, full 12 volts .. my neighbors must like me by now .. i think ive tried to start it a good 20 times now .. i hate germlins.

thanks for the help.