mattd04

I've spent the past few days searching the forums here, researching online, and watching numerous YouTube videos, so I did the best I could to do research before creating a new thread, here.

For the past few weeks, whenever I try to start my 2000 coupe, the instrument panel flickers and the gauge needles flutter. The car won't start on the first try, even after leaving the key in the ON position for a moment.

Starting 2 days ago, things seem to have gotten worse. The instrument panel still flickers. The A/C works fine, and there's no dimming in the HVAC display. However, I'm now seeing:

solid check engine light
Service ABS
Low Voltage
Reduce Engine Power
Check Gauges(Not all simultaneously, but each warning has illuminated).

I have a total of 4 keys for my C5

My dad has 5th key (full-size OEM key) that seems to work fine. While the 3 spare keys with the small heads appear to have smaller resistors than the OEM key, most of them produce the same flickering of the dash and the numerous warnings. The key at the bottom of the picture won't even turn (wrong VATS code, maybe idk).

I've pulled codes, twice. These are the codes I got the 1st time:

C1278 H - Traction temporarily cut by PCM
C1281 H - Steering sensor uncorrelated
C1288 H - Steering position sensor circuit
B2282
B2283/2285/2265 H 12V power feed 1&2
B2284 H
U1016 H - Normal software function?

I took a video of codes today and yesterday. I can post if necessary.

Overall, could this be something like a bad ignition switch, keys with bad/incorrect resistors, a grounding issue, or something else?

C5 Diag

Sounds like maybe a bad ignition switch…had a member 2 weeks ago whose IPC was flashing like a strobe light…he had a bunch of unrelated DTC’s and all DTC’s circuits were powered by one of the 4 wires in the ignition switch…if you have a DVOM and know how to use it I’ll show you how to check !!

mattd04

Thanks!

I don't have a multimeter yet, but I'll be buying one in the next few days, before I start taking stuff apart.

BigGun

Before you start taking things apart check your battery connections both at the battery and at the starter.

jim993

Yes, check battery connections, 11 foot pounds per Factory Service Manual. Also make sure that the cable connections at the battery are physically tight. In the past there were some batteries made with shallow bolt holes--- even though the bolts were tight, the cable was not tight against the battery. You should not be able to move a battery cable at the battery by hand if all is tight.

xlst

I had almost same problem as yours. It was caused by bad ignition switch. Heres link to my thread with instructions what to test and do https://www.corvetteforum.com/forums...car-start.html

rrwirsi

Along with everyone's suggestion, try squirting some CRC MAF Sensor Cleaner in the ignition key hole. I had starting problems 4 years ago and I used the CRC Sensor Cleaner as my final attempt to fix the problem before replacing the ignition switch and it worked. No further problems. I squirt the key hole 2 times a year as part of my maintenance procedure.

mattd04

Update:

I may still replace the ignition switch in a couple weeks, as I have a new switch coming, AND I'm researching how to fix a fallen mirror in my C5's HUD.

However, having used a different key today and starting the car 3 times, I have had NO flickering or warning lights, and the car has always started on the 1st attempt. It may just be my eyes, but the resistor on this particular key seems to be thicker/less worn than the others.

Very strange.

EDIT: Never mind. That key produces the same problem.

mmartinez

The resistor in the key is read by the BCM which in turn provides a ground connection to the TDR and sends power thru it's contacts to the starter solenoid. The flickering lights is mostly likely being caused by dirty contacts in the Ignition switch.

KOZ

New switch

Smoken1

You could try this
https://www.corvetteforum.com/forums...ch-repair.html

mattd04

Update:

The ignition switch has been replaced. When I started the car this AM, prior to replacing the ignition switch, (I don't know how else to describe it ( I could almost feel as pulsing or stuttering from the ignition switch). Now, it's gone, as well as the flickering instrument panel, and all the crazy warning lights.

Thank you all for your help. Here is a picture of the old switch. The contacts are clearly worn.