heater/defrost fan won't stop blowing !

[fatbloke-dim]

Just took my '93 out for it's annual test . Found one busted exhaust hanger , nothing a little weld would'nt fix . The battery cable was disconnected on the negative side , and when reconnected , the defroster fan was blowing . This with the heat/vent selector switch showing "off" . Selecting a heat or cool control causes the HVAC ot act accordingly ,but even when the system is switched off , and the ignition is off , the blasted fan blows up the defrost outlets , same when disconnecting the battery and re-connecting it . Does this suggest the welding may have fried something ? All was well prior to that . Any suggestions ,other than leave 'Vettes alone , I'm not to be trusted with 'em ?!!?!:eyerole

 

[fatbloke-dim]

Cheers for that , Vetteoz . Hope it's that and not anything fried . Looks like an easy-access item ,too ,which makes me smell a rat ! Unless , of course ,that's another "unobtanium" part like the '93 ECM's . If this never-ending cold front and hail let up ,I'd get out there and have a look , ironically it's been fine and dry between fronts while I was in bed - been on nights - now I'm up , well , it's turned crappy ! I'd rather be in Oz . Cairns'd do it for me for the rest of me days !!

 

[boomdriver]

yessir,

I agree with vetteoz. That blower control module is a common fault in the opt-68 elec a/c control system. The sell for somewhere between $75 to $125 , depending on where you find them. Local parts houses are cheapest while the catalog stores and dealers get the most. IIRC...NAPA was pretty stiff as well...

Its probably toast, but its worth the trouble to pull the 2 plugs off and clean and reconnect just to make sure corrosion is not behind the failure. Somehow these wires manage to creep up and out of the plug just sitting there...Also, look for wires that are loose or not seated in the plug.

 

[fatbloke-dim]

Well.....

Just ordered the mod from Corvette Central , $70 . Not too bad , we'll see what our duty-men want to screw me for when it arrives . Could easily double that . What's that old gag about not thieving - the government hates competition ? Ain't THAT the truth !ad
The wires look O.K. and clean and well seated in the connectors ,so hopefully the mod will fix it . Boomdriver - did you post someplace else referring to a fuse on the blower case could cause this , or was it a different year of 'Vette ? Could be mistaken on that , I've read posts all over the place , and it takes very little to confuse my already addled brain these days !

Is there a recognised procedure for testing the relay/mods ,with a multi-meter ? I have had a quick look in the F.S.M. and did'nt notice anything to that effect . Does'nt mean it was'nt there , tho' .See last point in above paragraph . Is there a possibility that the current from the welder fried an already suspect mod , although the battery neg lead was disconnected ? Is it sufficient to just disconnect the neg lead , or are other measures required or recommended ?

Thanx all for your help , it's a nice feeling to know someone cares for 'Vettes and their owners , we can sometimes feel a little on our own in this septic isle if you own an individualists car !!

 

[fatbloke-dim]

VetteOz and Boomdriver........
Just fitted the BCM today , and relief all-round ! All works like a charm . Too easy !! Prob'ly should'nt have said that . So , ta v. much for your assistance . Right on the money . Got the new 'un from Corvette Central , $70 , but U.P.S. was $77 , but it got here in less than a week from ordering . Good service . Noted Ecklers wanted $135 .Now , about this poxed-up Limey weather.................

 

[boomdriver]

VetteOz and Boomdriver........
Just fitted the BCM today , and relief all-round ! All works like a charm . Too easy !! Prob'ly should'nt have said that . So , ta v. much for your assistance . Right on the money . Got the new 'un from Corvette Central , $70 , but U.P.S. was $77 , but it got here in less than a week from ordering . Good service . Noted Ecklers wanted $135 .Now , about this poxed-up Limey weather.................

OUCH !

Glad it wasn't a new set of heads....

So your proper weather is a mess 'eh? Here as well. Some states suffering freezes while less than 1000 miles away record heat.
I think we've (mankind) have seen the last of "normal" predictable seasonal cimates. Its gonna be a weather mans guessing game from now on. But I am relieved to know that there is no such thing as global warming....'cause my elected political leadership has assured me of this.....:eyerole ........spilled milk if ever.


Glad you're back on the road and glad to have been of help.

 

[fatbloke-dim]

OOh yeah , weather......
After yesterdays extra-savage gales and sleet/heavy rain , today has been nice 'n' sunny , and temps hit a dizzying 66 degrees in old money . So - Ol' Blue went out for a little spin . Thought I'd go to the airport , there's a pub right at the end of the runway , a bit overrun with the local dead-beats and their chimp-like offspring , but last time there 10 years ago , the ale was still good . Shock-horror!! The pub car park has gone pay to park , even for customers . That blew it for me . At least I got to boot it thru' the tunnels under the 2 runways , just to hear that beaut sound with no other traffic near me . Not all cars here have a real engine , most are 4-pots , most have ridiculously large tailpipes that make a hellishly loud asthmatic farting/gargling sound . Although having said that , I passed a yellow C5 or 6 , and pulled up at the motorway on-ramp next to a Viper coupe - the only good-looking Viper in my opinion , is it a GTC or something ? Would have tried to uphold the honour of Chevy , but was spooked by a rather anonymous BMW behind me , acting out of character - most Beemer driver here seem to think they've really got sumptin special , but this guy hung behind me when he could have passed . Thought so.....a mile down the road , the blue lights came on and off he shot to a mega-pile up a mile in front . Jeez , that was a mess - about 8 fire engines , countless ambulances and 2 helicopters . Did'nt know we had any air ambulances in these parts . Ol' Blue performed most satisfactorily .
Thanks again for sage advice , and I'm glad it was'nt a set of heads I'd needed !! Still did'nt end there , tho' , had to pay £20 import and tax . The screw never stops turning , eh ?:eyerole

 

[John Robinson]

OOh yeah , weather......
After yesterdays extra-savage gales and sleet/heavy rain , today has been nice 'n' sunny , and temps hit a dizzying 66 degrees in old money . So - Ol' Blue went out for a little spin . Thought I'd go to the airport , there's a pub right at the end of the runway , a bit overrun with the local dead-beats and their chimp-like offspring , but last time there 10 years ago , the ale was still good . Shock-horror!! The pub car park has gone pay to park , even for customers . That blew it for me . At least I got to boot it thru' the tunnels under the 2 runways , just to hear that beaut sound with no other traffic near me . Not all cars here have a real engine , most are 4-pots , most have ridiculously large tailpipes that make a hellishly loud asthmatic farting/gargling sound . Although having said that , I passed a yellow C5 or 6 , and pulled up at the motorway on-ramp next to a Viper coupe - the only good-looking Viper in my opinion , is it a GTC or something ? Would have tried to uphold the honour of Chevy , but was spooked by a rather anonymous BMW behind me , acting out of character - most Beemer driver here seem to think they've really got sumptin special , but this guy hung behind me when he could have passed . Thought so.....a mile down the road , the blue lights came on and off he shot to a mega-pile up a mile in front . Jeez , that was a mess - about 8 fire engines , countless ambulances and 2 helicopters . Did'nt know we had any air ambulances in these parts . Ol' Blue performed most satisfactorily .
Thanks again for sage advice , and I'm glad it was'nt a set of heads I'd needed !! Still did'nt end there , tho' , had to pay £20 import and tax . The screw never stops turning , eh ?:eyerole

And that is why we love these cars so much. It is just for days like that.