How to check CEL without scanner
 

Hey guys,

I know the info is available somewhere, can you help me find it quicker?

Short story:
Noticed on my way home that CEL is on now, but scanned gauges, nothing seems out of sorts.

Get home a few minutes later, and the water temp gauge is almost pegged!! THEN the DIC notifies me that the A/C has been turned off due to overtemp condition. Engine still running, I popped hood right quick to see if I can hear the fan running. No joy. Turned off the engine and a little later the relief valve on the coolant overflow tank is spewing, and spewing. Now most of that is on my driveway, and the tank is 3/4 empty.

:mad: :mad: :mad:

Is there a quick way to tell what the culprit is?? Relay seems ok, but don't know if the sensor, or switch, or fan itself is bad. Have a call into dealership now to fix tomorrow, but want to have some info of my own ready. On other cars I had, you could check by turning the key on and off 5 quick times, then read the codes thru the CEL flashes. Is there a way to do that on this car?

It's a 2007 base with LS2, manual trans.

I'm mostly pissed because just yesterday I spent over $1100 on the new rear cover on the diff. :mad: I don't need this shit.

I don't think there is a way to check codes via dash on C6s, but I could be wrong.

Autozone or Advanced, etc will read codes for no charge. Though unless you have one of those stores very nearby, I wouldn't drive it too far if overheating like that. Concern yourself with that first, and if CEL remains, tackle that next. May or may not be related.

If coolant was spewing, tells it really was running that hot (not a flaky temp sensor), and if the fans were not running in that condition, there's a certain problem. Fuses first thing to check. Relay...I don't know how much fan wiring changed from the C5, but I believe there's 3 relays at play for series/parallel fan control. Unfortunately, my service manual is stored on my dead computer, so I can't pull up a C6 schematic.

Thanks Tom!! :seasix:

I figured that it really did get that hot, and A/C was running fine if not a little too cold! So I can't figure out what's going on. Maybe fan wasn't running at all the whole trip home.

Sure seems suspicious that out of the last 3 times I brought car in for service, the last 2 had some different problem afterwards.

This sucks. :(


ETA: Just did experiment putting car all the way into garage. Turned on A/C and no fan. Now I think it's a power problem, not a sensor problem.

In the power box under hood, I only see the one relay for the cooling fan (60A mini relay) If I could figure out how to get it out, I'd swap with the one next to it and see if the problem moves, or fans turn on. Is there additional paths to consider?
Is there a way to force the fan on run without the engine running?

Sorry, I still don't have the manuals for this car yet. :(

Checked my 2006 service manual. Found the code list in the back of vol 3. But it does not give an alternate way to check codes other than with a scan tool.

Thanks Wendy. Drat! If I had gotten the scan/tuner tool like I had meant to a few months ago, this would be a non-issue.
But, Nooooooooooooooooooooooo!

:D

Nope that was a "BIG improvement:over the C5, no way to check codes without a scanner.

They just want you to see Mr Goodywench for everthing!

Great. :rolleyes:

It's all good now, was the fan control module. F'k, only $400 later, back on the road.

:(