The other day my 2001 C5 wouldn’t start. After trouble shooting for a few days and reading through A LOT of the forum I think I’m getting closer…? Here is how it all started… when I got in my car the security signal would be blinking until I shut the door. Then it would go out. I’d turn the key and see the Corvette thing and keep turning…. And nothing. You could hear some relays clicking from the passenger floor and a pump turn on, but that was it.

So here is what I have done:
I got all of my codes first:
10-pcm no codes
28-tcs
c1225 h Wheel Speed Sensor Circuit
c1241 h MAGNA STEER Circuit Malfunction
c1283 h VSES Sensors Uncorrected
40-bcm b2723 h PASS-Key Detection Circuit
58-sdm no codes
60-ipc no codes
80 radio no codes
99-hvac b0333 c h Outside Air Temperature Sensor Open
a0-ldcm
b2252 h Door Key Cylinder Circuit
b2202 h Window Switch Circuit
b2206 h Window Switch Circuit
b2208 h Window Switch Circuit
b2282 h Battery #1 Circuit
b2284 h Battery #2 Circuit
b2262 h Mirror Position Sensor Signal Circuit
b2264 h Mirror Position Sensor Signal Circuit
u1255 h Class 2 Communication Malfunction
u1064 h Lost Communication with XXX
u1016 h Lost Communication with XXX
u1096 h Lost Communication with XXX
a1-rdcm
b2283 h Battery #1 Circuit
b2285 h Battery #2 Circuit
u1255 h Class 2 Communication Malfunction
u1064 h Lost Communication with XXX
u1016 h Lost Communication with XXX
u1096 h Lost Communication with XXX
a6-scm
b2606 h Seat Position Sensor Circuit
b0-rfa
c2100 h Lost Communication with XXX
c2115 h Lost Communication with XXX
u1000 h Class 2 Communication Malfunction
u1255 h Class 2 Communication Malfunction
u1064 h Lost Communication with XXX
u1096 h Lost Communication with XXX
u1016 h Lost Communication with XXX


I then cleaned the two ground connections under the hood. I checked all of the fuses under the hood and floor board. I turned the ignition on and verified I had battery voltage across fuse 19,18,17,22,16, and 13 under the hood. I also checked 21,22,and19 in instrument panel fuse block. (FYI I don't have a (22?) on my 2001. It is blank on the schematic. There is a BCM fuse at 23?.

I then reset the VATS system doing the 10min-10s-10min-10s-10min-10s process.

Then I tried removing fuse number 25 and put it back in to reset the BCM.

Then I decided to get my battery checked because of the battery circuit code (history code). It only had 300 amps. I replaced it with a 700 amp. This didn’t help.

Then I Bill Curlee's post and removed my ignition switch lock cylinder and sanded the contacts. They were pretty black and I really did think this was going to solve my problem. I didn't check the resistance though. I didn’t check and make sure the all the little cylinder pins moved up and down the way they were supposed to in OFF-ACC-ON. I may need to go back and check this.

Then I tried the “depress the clutch and turn and HOLD the switch to start. While your holding it there, pump the clutch peddle on and off the "CLUTCH SAFETY SWITCH" and each time you make and break that switch,,you should hear the theft deterrent relay (TDR) in the passengers foot well click.” I can hear this!

Then I decided to check the voltage on the TDR relay, and had trouble finding it. I came inside to look at the TDR location and I got distracted and decided to reset my codes and see if I had any new codes, and something very interesting happened…

Now when I put my key in the ignition and turn it one click right where it should normally say “CORVETTE”.. it doesn’t say anything it is just black. I can try cranking it and I get the same result I have been getting. The battery gauge is also reading 8V. I checked the battery and it has 12.5Volts. I CAN’T EVEN GET MY CODES ANYMORE!!!!!!! It won't display anything. Then I pushed gauge and the display got stuck showing my mileage and I couldn't get it to change.
I’m thinking maybe I moved the BCM a little looking for the TDR relay and now there is a loose connection.

Anyways the next thing I’m going to do is check and see if I have 12V on the purple wire of the TDR relay and get a new VATS pellet key. I checked the resistance across the two pellets and it is VERY DIFFICULT to get a consistent reading. Unless I forgot how to read a voltmeter it jumps between OPEN and 70-170ohms. So I think I need a new key, but I still probably have something else going on. I’m now wondering if the display not showing me the codes and telling me my battery voltage is zero means that the BCM or something else is dead.

 

Have you checked ground wire on driver side of block.

 

Clear all those codes. They are all H as you wrote them. The ign. switch sure seems like a good possibilty. Check your codes after clearing all and do it with the ign switch still on.

 

I have not checked the drivers side engine block ground. Right now I can't get my codes. When I turn the key it attempts to say "Corvette..." but gets to the "Cor..." part and then turns black. It won't do anything when I do "options-fuel x4".

 

The positive cable from the battery needs to be tight at the stud next to the engine fuse box.

 

Today the display worked fine. There aren't any new codes. I cleaned the ground below the battery. I also verified that I get battery voltage on the 12 gauge wire from the TDR. I also checked for battery voltage at mini fuse 14 and 52 in passenger footwell, and there isn't voltage on 14. I was thinking there should be after looking at the wiring diagram, but maybe I'm mistaken. I also opened the ignition switch up again. I verified that the cylinder pins are moving up and down correctly.

I don't have the ability to jack the car up and get to the solenoid or I would check that I'm getting there. Very soon I may have to do this though.

I'm going to check the ground in the driver side door tomorrow. Does anyone know if fuse 14 should have 12.5VDC on it when ON or Cranking..?

 

Ok. I'm not sure why you are pursuing the engine not cranking, because based on your codes...that is the least of your problems.


You need to focus on restoring communications via 12 volt/ground checks. ..and yes, the ignition switch feeds fuse 14, so 12 volts will not be present, until you rotate the key to start.

As suggested, reset codes, and see where you are at.

 

Lucky the only current code I have is 99-hvac b0333 c h Outside Air Temperature Sensor Open. Since I don't have battery voltage on fuse 14... and I have re-cleaned the contacts on the ignition feed switch, would that mean that it is possibly my VATS Key? Otherwise I'm going to keep cleaning grounds.

 

Ok, good. Glad you have most of the codes cleared. As I stated in my previous post, you will not have 12 volts on fuse 14, until the key is rotated to start. This is a direct connection from the ignition switch, to fuse 14. The VATS uses the lock cylinder, not the ignition switch electrical contacts.

 

Lucky, I don't have 12.5volts on fuse 14 when cranking. I'll verify tonight. So, if I understand you correctly it is the ignition switch and not the lock cylinder (VATS key).

I have cleaned the contacts but could see how the arms could still not be making contact. I'm thinking it may be G201. What are your thoughts?

So the lock cylinder reads the resistance from the key and sends this to the BCM?

If I wanted to check the lock cylinder reading the key correctly how can I do this? Can I check an output voltage somewhere?

 

Yes. If you reference the schematic I posted above, you can unplug the connectors from the ignition switch, and evaluate the resistance value between C1; pin B, and C2; pin A. When you rotate the key to start, you should have very close to 0 ohms.


You lost me. What does G201 have to do with the ignition switch?


Correct.






Yep. Using the schematic above, you can evaluate the resistance at at the lock cylinder connector, test the 5 volts from BCM, etc.

 

I took the ignition switch back apart, checked the alignment of the arms. Put the green cover back on and ohmed out all the arms/pins in off/acc/on/crank and everything appeared right. I put it back in the car and check fuse 14 and it gets battery voltage. I'm not sure if me taking it back apart fixed it or if my wife not having the voltmeter on the fuse pin was the problem. So, the ignition switch appears to be working. Is it time to jack up the car and check the starter solenoid?

 

Ok...never trust a woman with a meter....

Provided the security light is not on when you try to start, the next step is to make sure the TDR is energizing once the clutch pedal is depressed, and the key is turned to start.

 

I have 10.8V across the purple and yellow/black wires on the TDR and 12V on the battery. If I have 10.8V here doesn't that mean the Clutch Switch, PNR switch, and the ground provided by the BCM are all working correctly?

Is there anything else to check before jacking it up?

Is 10.8V a problem? I'm not sure if a 1.2V drop is reasonable or not.

 

You are probably reading a voltage drop, because of the ground you are using. You want the red lead on the purple wire coming from the TDR(back probing the connector), and a chassis ground......not the yellow/blk wire. In any case, it sounds like the TDR is in fact energizing, so the next step is checking the purple wire on the solenoid.

 

I just chose that ground to verify the BCM was working right. I was thinking the BCM had the ability through that ground to prevent a start. Does the solenoid get its ground from G104/108? For some reason I had just convinced myself the solenoid ground came from that yellow/black.

 

Sounds like you're having the same problem as me. In the last 3 days I've had to push start the car at least 6 times. (I'm on a road trip far from home and don't have many tools) please keep us posted on your progress.

 

No. The solenoid is grounded through the starter, which in turn, is grounded by the block.

 

Great read guy's. This level of troubleshooting is far better than you can trust from most mechanics, especially most dealerships.

Time to jack that sucker up and check the solenoid connections and grounds.

 

Good news and bad news. I jacked the C5 up today and could definitely hear the solenoid engaging but no start. I gave it a few bangs with the hammer and it didn't start the first time, but it started on the fourth time. I let it run for about 5 minutes, and then...

it started leaking water everywhere. Not sure what to do now. My AC belt was making noise when I turned the AC on. But its time to start diagnosing this problem now...