Error Code 33 Info

[btr85vette]

I recently had a problem where my 85 Vette suddenly would barely run. I checked the error code, and it threw a code 33, MAF sensor voltage high. I bought a FSM from Ebay, and went through the diagram, and found something interesting.

After going through the diagram, and tearing part of the car apart to find the Burn Off module, I happened to notice on the wiring diagram in the FSM that there was a circuit going to the gauges. So I went to the fuse block and found a 10 amp fuse for the instrument panel, and it was blown. I replaced it and the car ran fine again. I had one of the instrument panel bulbs blow, so maybe they're related.

The whole point of this post? While the FSM has great info, it NEVER said to check the fuse! I spent a week and a half with my car down, and all I had to do was replace a fuse.

Long story short, on an error code 33, check the Instrument panel fuse first.

(and yes, I know, I will be monitoring the circuit to see why the fuse blew.)

 

[Hib Halverson]

While I'm the first to advocate use of the FSM in diagnosis, I'll admit that the manual doesn't always remind us to use common sense.

For example: a couple of months ago I was troubleshooting the from lamps my 01 Camaro. The circuitry of the day time running light system on those cars is similar to that on a C5 in that the directional signals double as the DRLs.

Both signals and DRLs failed. The FSM led me to either the DRL module or the directional signal switch. So I tore apart the center stack to get at the DRL module--it was ok. Then I tore apart the column to get at the signal switch which was also ok.

I has assumed a simultaneous double bulb failure would be unheard-of so I troubleshot the rest of the system first.

Actually, both bulbs did burn out at the same time.

Silly me.

The lesson is (well....duh): always add a little common sense to what the book says...or doesn't say as the case was here...and check fuses and bulbs first.

 

[CROOZ1N]

yup always check the easiest stuff before diving headfirst into the deepestdarkest part of the problem. We have a couple of guys that I work with and they seem to forget the easy stuff and make a simple problem much harder than it really is. And sometimes we can get so focused on the problem that we seem to have blinders on leading us down an incorrect path without knowing it. Also its a great idea to keep notes when troubleshooting. That way 2 hours from now when you are scratching your head you can retrace what you've already done and it may lead you to that one step you may have overlooked.

Good Hunting!!