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Very Strange "Car won't start sometimes" problem

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Old Jul 14, 2011 | 08:49 PM
  #81  
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Originally Posted by Aviator54
Actually it sounds like the pickup sensors in the ignition switch. Trying the other key probably won't fix it but bypassing the VATS sensor will fix that particular problem. I just went to radio shack and bought the correct resisters, soldered them to a circuit board and put in a hidden kill switch under the dash my wife doesn't know about...
SOunds like a good plan...but I saw someone say they can disable VATS in tuners right?? getting the car tuned next week so I will have that turned off!
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Old Jul 14, 2011 | 08:56 PM
  #82  
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Take the KEY SENSOR off the ignition switch,, take it apart and bend the tabs in side so it reads the resistor chip better!

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BC
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Old May 12, 2012 | 07:48 AM
  #83  
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Default No clicking

Originally Posted by Bill Curlee
Try this: When you have the NO START issue, turn and hold the key to START and while your holding it in start, pump the CLUTCH Peddle on and off the clutch safety switch. When you do that you will hear the Theft Deterrent Relay in the passengers foot well click. That proves all the components up to and including the relay coil is good.

Heres a picture of the relay:




Its the relay with FOUR wires. Yellow, Yellow/Black, Red and PURPLE
Hey found this and tryed to pump clutch switch and DO NOT hear clicking at Theft deterrent relay. Is that relay bad or somethink esle is not sendind power to sw???????
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Old May 12, 2012 | 07:56 AM
  #84  
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Originally Posted by helga203
Hey found this and tryed to pump clutch switch and DO NOT hear clicking at Theft deterrent relay. Is that relay bad or somethink esle is not sendind power to sw???????
I swaped relay with the one next to it and relay is good i'm not getting 12v to theft relay where to look now????????
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Old May 12, 2012 | 08:22 AM
  #85  
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Default got it

Found the problem it was a mini fuse to ingition sw. Thanks for helping
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Old Oct 3, 2013 | 02:26 PM
  #86  
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Originally Posted by Bill Curlee
It could very well be something else, Poor connection at the solenoid could be one possibility, Bad TDR, could be another. Thats why,,, it is very important to do a bit of troubleshooting with a meter.

The schematic provided is the key...

To provide an answer to your question "Doesn't the fact that my car will eventually start mean that the solenoid is good, and its probably something else???

ABSOLUTELY NOT! The solenoid coil will read fine but the spool (inside the solenoid) will not retract when power is applied. Trust me... I have one on the work bench just like I explained.. I just changed the $50 solenoid and solved all of my no start issues.

BC

What you can do is BUMP the starter/solenoid with a long wooden rod while someone holds the key to start (when it fails to start). If the solenoid is failing mechanically, agitating it mechanically will make it start the engine

Bill was spot on with this diag I started chasing vats but found start switch engaged no voltage to the thick purple wire..jumped to red no solonoid click but jumped heated right up. bad relay caused by bad Sol. I'm afraid to bump it for fear of it not disengaging and rushing to disconnect the bat.
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Old Oct 3, 2013 | 11:16 PM
  #87  
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where was this mini fuse located?
just in case I ever need to check it...
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Old Oct 4, 2013 | 12:07 AM
  #88  
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There are only TWO fuse boxes in the car.... Under the hood and passengers foot well:

Heres the schematic that you need and it tells you where ALL the fuses are for the starter circuit:

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Old Nov 20, 2014 | 09:14 AM
  #89  
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Originally Posted by Bill Curlee
There are only TWO fuse boxes in the car.... Under the hood and passengers foot well:

Heres the schematic that you need and it tells you where ALL the fuses are for the starter circuit:

I'm having very similar and related issues. Incredible knowledge in this thread. Thanks everyone for sharing.

BTW: When I am experiencing the no-start issue, typically, after a few attempts, the car starts by "bumping" the manual shifter, while in neutral, to one side or the other. ie: move it back-n-forth. Car will typically fire right up when doing that. Very consistent with the shifter bump trick, but still have not figured out exactly what the real issue is. Saturday I'm having it looked at.
(I just purchased the car used about 5 months ago.)

Last edited by slimflem; Nov 20, 2014 at 10:15 AM.
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Old Nov 23, 2014 | 09:00 PM
  #90  
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Default No start - your fix

Related thread to OP's last post #79
http://forums.corvetteforum.com/show....php?t=3183336

Died and would not start
http://forums.corvetteforum.com/show....php?t=3670906
Fix was post 21, not post 12

For Chassis Ground Problems check your Chassis Ground Connectors
http://forums.corvetteforum.com/showthread.php?t=896875

Last edited by cor28vettes; Nov 17, 2015 at 10:30 PM.
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Old Apr 4, 2015 | 01:28 PM
  #91  
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Thanks for this thread, just went through this on mine and it was just a bad theft deterent relay. Volt meter & a little testing, new relay & Im back in action.
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Old Sep 12, 2016 | 11:51 AM
  #92  
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Default good to keep this thread going...no pun intended

Originally Posted by Aviator54
Actually it sounds like the pickup sensors in the ignition switch. Trying the other key probably won't fix it but bypassing the VATS sensor will fix that particular problem. I just went to radio shack and bought the correct resisters, soldered them to a circuit board and put in a hidden kill switch under the dash my wife doesn't know about...
Look for VATS key sensor coming apart inside ignition cylinder. Other member had this as a fix. He replaced both sw & cyl.

These C5's are aging. Stuff wears out/happens.
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Old Oct 10, 2019 | 11:01 AM
  #93  
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Default I have the same problem

[QUOTE=BIGTACO;1576587186]Sometimes when I go to start my 2003 C5 Z06 the car will not start. I turn the key and everything comes on as it should but nothing. I wait a bit, turn the key 5 or 6 more times, wait a bit more, turn it 2 or 3 more times, and BAM it starts right up. This happens very sporadically. Sometimes it happens once a month. Sometimes it happens once a week.

Anyone have any ideas what it could
is this where I reply?

I’ve had the same issue. I think I had a couple of years ago took it to a garage and they thought it was something else fixed it, but as you know it fixed itself, for A period of time

so on interesting video on YouTube where the guy had the same problem he replaced the starter and he seems happy with that. But maybe he’s having the same remission we’ve all had For 100 bucks I’ll try fixing the starter

I went through the codes there’s no codes there to help you

Last edited by lloydainey; Oct 10, 2019 at 11:02 AM.
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Old Apr 21, 2021 | 02:57 PM
  #94  
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Default My corvette did the same

Originally Posted by BIGTACO
Sometimes when I go to start my 2003 C5 Z06 the car will not start. I turn the key and everything comes on as it should but nothing. I wait a bit, turn the key 5 or 6 more times, wait a bit more, turn it 2 or 3 more times, and BAM it starts right up. This happens very sporadically. Sometimes it happens once a month. Sometimes it happens once a week.

Anyone have any ideas what it could be???

my 2001 corvette did the same thing had to have it towed home. Checked the codes with a code reader nothing came up. Now this car has had major work done last 2 yrs 15,000 worth the engine, drive train ect. So I'm thinking what could possibly be wrong checked the codes on the dash she read security system fault. I remembered my bf motorcycle fobs battery was low and it would basically do the same thing and not start. I decided to start small work my way up . Well the fob was working fine but well what the heck spent 4 bucks on a new key fob battery and she started right up. Sometimes the most simple craziest things can be the problem.
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Old Jul 12, 2021 | 12:53 PM
  #95  
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Default C5 wont start unless ignition is momentarily set to "on," first

Lately, my 2000 C5 sometimes won't start, even though I've had it hooked up to a trickle charger all week.

If I stick the key in the ignition and immediately turn it to the start position, the engine won't start. After I switched to a spare key, the same thing happened. However, if I leave the key in the ON position for a brief moment, the car will start without a problem. Does anyone know what could cause this? I saw the following codes in diagnostics mode.

B2282 HB2283 HB2284 HB2285 HU1064 HU1016 H
I don't see any visible corrosion on the battery or the grounds in the engine bay. The voltage meter shows a consistent reading of 13-14 volts once the car starts.
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Old Jul 12, 2021 | 01:48 PM
  #96  
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This is a very old thread you have posted on, you should turn the key to the on position and let the gauges sweep and the various indicators turn off before turning the key to the start position.
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Old Jul 12, 2021 | 02:06 PM
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Originally Posted by mattd04
Lately, my 2000 C5 sometimes won't start, even though I've had it hooked up to a trickle charger all week.

If I stick the key in the ignition and immediately turn it to the start position, the engine won't start. After I switched to a spare key, the same thing happened. However, if I leave the key in the ON position for a brief moment, the car will start without a problem. Does anyone know what could cause this? I saw the following codes in diagnostics mode.

B2282 HB2283 HB2284 HB2285 HU1064 HU1016 H
I don't see any visible corrosion on the battery or the grounds in the engine bay. The voltage meter shows a consistent reading of 13-14 volts once the car starts.
PLEASE start new thread with your concern !!
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Old Oct 15, 2021 | 11:45 AM
  #98  
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Originally Posted by BIGTACO
Sometimes when I go to start my 2003 C5 Z06 the car will not start. I turn the key and everything comes on as it should but nothing. I wait a bit, turn the key 5 or 6 more times, wait a bit more, turn it 2 or 3 more times, and BAM it starts right up. This happens very sporadically. Sometimes it happens once a month. Sometimes it happens once a week.

Anyone have any ideas what it could be???

My 2004 does the same exact thing. I would like to add when I turn the key to start the volt gauge drops to almost zero. This tells me the starter is defective. I did have the starter replaced and it worked great for about 3 months then the problem resurfaced. I believe the dealership that replaced the starter with a rebuilt stater the starter is still the problem. The dealership is still troubleshooting to see what the problem is. They don't understand that rebuilt and new parts are sometimes defective. Folowing.
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Old Oct 16, 2021 | 01:12 AM
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In my honest opinion, You need to start troubleshooting at the Theft Deterrent Relay (TDR). That is the HEART of the cars starter circuit. The TDR is located in the passengers footwell behind the Toe Board. Open the toe board and locate the Fuse Box and Body Control Module (Big Silver Box to the left of the fuse box) Above the BCM and Fuse Box on the fire wall are some relays. One of them is the TDR. The TDR relay has FOUR WIRES ( RED, PURPLE, Yellow & Yellow/ black stripe wire ) The RED Wire is the HOT wire that is hot at all times. The PURPLE wire goes to the starter Solenoid and is only HOT when the relay is energized. The yellow wire is energized when the the ignition key is in the CRANK / START position and the clutch safety switch is energized (clutch fully depressed) The yellow black stripe wire is the relay ground wire. Its only grounded when the BCM sees ALL of the requirements to properly start the engine. ( Proper Ignition Key VATS pellet inserted into the ignition switch and BCM and PCM are properly hand shaked.)

You can use a JUMPER WIRE and jump between the RED and PURPLE wire. When jumped, the starter solenoid should energize and the starter should crank the engine. NOTE AND WARNING!!!!! The Transmission MUST be in NEUTRAL and the wheels chalked to prevent vehicle movement!!! If the vehicle is in gear, it will MOVE when the relay is jumped!!!
If the ignition switch is in the RUN POSITION and the relay is jumped, the engine should crank and RUN. NOTE AND WARNING!!!!! The Transmission MUST be in NEUTRAL and the wheels chalked to prevent vehicle movement!!! If the vehicle is in gear, it will MOVE when the relay is jumped!!!

You can short the yellow black stripe wire to chassis ground temporarily to by-pass the BCMs security requirements. That will allow you to see if the BCM is grounding that wire to allow the low current side of the relay to function and pull in the relay contacts to energize the coil and close the high current relay contacts to energize the Starter Solenoid on the starter.

NOTE! If you turn the Key to the CRANK POSITION and Depress the clutch and release it, each time you fully depress and release the clutch, you SHOULD hear that TDR click Energize and turn off. The Clutch Safety Switch is located on the fire wall and is closed when the clutch peddle contacts it. Those switches fail quite a bit because the contacts inside the switch get corroded. I took mine apart and cleaned it. Good as new! :-)

Hope this helps.

Bill Curlee

Last edited by Bill Curlee; Oct 16, 2021 at 01:16 AM.
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Old Oct 16, 2021 | 11:26 AM
  #100  
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Great to see a post from you Bill, I didn't know that the PCM to BCM handshake had to be present in order for the BCM to ground the TDR coil, I keep learning something new everyday.
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