Hello everyone and thanks in advance for any insight. I have just recently visited some family and my step mom has a 1999 Corvette C5 sitting in the garage with 27K original miles on it. It was on its 2nd battery and it was dead. We replaced the battery today and runs great however the AC and Radio don't work. The AC is the model without the adjustment *****. The digital screens work and shows everything but no air comes out of any vent. The AC fuses looked fine as well. And for the radio it doesn't turn on or anything and I don't see a lock or anything on the screen. Am I locked out of the system somehow or am I looking at something more serious? I read that a leaking AC Delco batery could cause damage to the wiring and ac hose but I couldn't find any leaks and didn't see and corrosive damage.

 

Start with the fuses first. Pull the codes next and post them here. In the engine compartment, there is a small black plastic tube that connects from the MAP sensor on the rear of the intake and goes down past the back side of the battery to the firewall. If that line is cracked, melted from acid or similar, the HVAC valves will not work. There is a re-sync procedure that someone in here has to take care of the HVAC system once there's vacuum to it again. The AC Delco batteries that I heard about and the one in my '99, the positive terminal would litterally fall off the battery leaving a nice gaping hole in the side of it where the acid would immediately start dripping out.

 

Checked the plastic tube and it seemed fine. As for the fuses, all seem ok under the hood. Is there an alternate fuse box elsewhere? As for the codes these are what came up:

10-PCM - No Codes

28 TCS - c1255h

40 BCM - b0502h, b0507h, b2482h, b2587h, b2588h, b2592h, b2593h

58-SDM - b1001h

60-IPC - No Codes

80-Radio - No comm.

99 HVAC - No Codes

AO-LDCM - b2282h, b2284h, u1064h

A1-RDCM - b2283h, b2285h, u1064h

A6-SCM - b0851h, b2860h

BO-RFA - u1096h, u1064h, u1016h

Thanks again for the help

 

Theres a fuse box at the front of the passenger foot well.

 

All history codes. Please clear them all out, and try again. Make sure door locks, windows, etc are working on both sides.

 

I have an 90 with the same problem. Passinger door was not closed all of the way and interior lights ran the battery down. I charged the battery but now the AC fan will not come on in higher speeds and the radio comes on holds presets and time but no sound. The fuses on the passinger side of dash are all good. Now what?

 

Your post says a '90? I can't help you there unless its a typo and really a C-5 of some year. Check your battery with a volt meter and make sure its up to 12.5vdc static across the battery with everything turned off. Pull your codes and post them. In those codes, look specifically any ending with a "C" for current. "H" codes are history codes. Clear them all and see what comes back.

For the OP above, as already mentioned, there are two fuse boxes. One in the engine compartment as you know already and another under the floorboard of the passenger side.

 

C1255 EBTCM Internal Malfunction
B0502 RH DRL Relay Circuit
B0507 LH DRL Relay Circuit
B2482 Backup Lamp Relay Circuit
B2587 Column Lock/Unlock Drive (A)
B2588 Column Lock/Unlock Drive (A)
B2592 Column Lock/Unlock Drive (B)
B2583 Column Lock/Unlock Drive (B)
B1001 "I didn't find it"
B2282 Battery #1 Fault
B2284 Battery #2 Fault
U1064 Loss of Communications with BCM
B2283 Battery #1 Fault
B2285 Battery #2 Fault
U1064 Loss of Communications with BCM
B0851 Battery 1 Out of Range
B2860 "I didn't find it"
U1096 Loss of Communication with IPC
U1016 Loss of Communication with PCM
U1064 Loss of Communication with BCM

So all this appears to point to either a low battery voltage or a shorting wire in one of the doors, inside of the accordian tube. That wire will short to the frame and cause the loss of comm for the door control modules and a host of other issues as its the databuss comm line. This failure may also be pointing to a bad ignition switch. I want you to send a PM to Bill Curlee on this and get his input as he's the best in here for electrical issues.

 

Something else, open up the passenger floorboard access panel and look for water or evidence of water on the BCM at that location. If there is water, there is a lot more to do but if so, check the udders that drain the water condensation from the HVAC system. Fixing things with the BCM are more involved, but look there for water first.

 

Thanks for the reply. My vette is a 1990 C4. Still looking for the problem.

 

Then my advice maybe totally out the window for you as it was for a C-5 and not a C-4. You would be much better off posting in the C-4 section where someone more familiar can assist you.

 

I searched on "Dead Battery No radio or air" and it brought up all of the forums.
Thanks

 

Thanks for all the help, I am out of town so its gonna have to wait for now. Haven't checked the passenger side fuse box yet. Hopefully Ill be able to get to it soon

 

Finally managed to have the family check out the car. No evidence of water in the passenger side floor panel. Checked fuses there as well and the radio was blown and is now working. The HVAC fuses all look fine. Could it be a HVAC maxi fuse or is it something with the compressor that is causing the ac not to blow. It sounds like its making some noise but nothing coming out. All the door locks and windows work as well.

 

Hi, If I read you right you are saying that, with the system on there is no air coming out of any vent. Is this with both the heat or ac on? And you are not saying that air is coming out all the vents at the same time. What this means is that your fan motor is either not engaging, or is engaging and is blocked from turning. Also if you changed the battery make very sure that you have a good tight clean connection at both terminals, sometimes the terminals are not tight because the screw is to long for the terminal hole, or the rubber shield gets in the way. Also check the cables for tightness at the starter lugs and fuse box underhood. When you are sure all those are tight then check in the underfloor fuse box for mini fuse 18, and maxi fuse 49 and 51. Then check the fan relay,it is in the pass side footwell, mounted on the multi use relay and fuse bracket, above the Body Control Module . If all these check out, you need to check the fan motor itself and the blower control module attached to it. Access the fan, and check to see that it isn't blocked by debris or small animals, and unplug the connector, and apply 12 volts to the hot terminal and ground it and if it is good it should spin, leaving the blower control module as the likely problem.
Below is a diagnostic from the manual if you want to go that route.
And I should add that you may have a bad ground connection, and the following grounds should be checked for tightness and cleanliness.
=====================================
G102
Forward lamp harness, on the top of the RH frame rail, behind the RH headlamp assembly, ground for SP100 (CKT250)


G201
Instrument panel harness, at base of LH A-Pillar, ground for SP201 and SP203 (CKT 150 and CKT 351)


G202
Instrument panel harness, at base of RH A-Pillar, ground for SP202 (CKT 150)

=====================================
Good Luck
++++++++++++++++++++++++++++++++++
Blower Motor Inoperative at Any Speed
Blower Motor Inoperative at Any Speed <<C60>> Step
Action
Value(s)
Yes
No

DEFINITION: Blower motor is inoperative at any selected speed.

1
Were you sent here from the HVAC System Check (C60)?
--
Go to Step 2
Go to HVAC System Check

2
Disconnect the blower motor connector.
Turn the ignition switch to the ON position.
Place the HVAC mode switch in the UPPER position.
Turn the blower switch to the LO position.
Connect a DMM between terminal A of the blower motor connector and a known good ground.
Measure the available voltage at terminal A of the blower motor connector.
Is the voltage within the specified values?
10.0 -14.0V
Go to Step 3
Go to Step 10

3
Connect a DMM between a good ground and terminal B of the blower motor connector.
Measure CKT 150 for continuity to ground.
Is the resistance to ground less than the specified value?
0.5ohms
Go to Step 4
Go to Step 5

4
Replace the blower motor. Refer to Blower Motor and Fan Replacement .

Is the repair complete?
--
Go to HVAC System Check
--

5
Disconnect the blower motor control module connector C2.
Connect a DMM between the blower motor control module connector C2 terminal 2 and a good ground.
Measure CKT 150 for continuity to ground.
Is the resistance to ground less than the specified value?
0.5ohms
Go to Step 6
Go to Step 7

6
Locate and repair an open or a high resistance in CKT 150 (blk wire) between the blower motor connector and the blower motor control module connector C2.

Is the repair complete?
--
Go to HVAC System Check
--

7
Disconnect the blower motor control module connector C1.
Connect a DMM between the blower motor control module connector C1 terminal E and a good ground.
Measure CKT 150 for continuity to ground.
Is the resistance to ground less than the specified value?
0.5ohms
Go to Step 8
Go to Step 9

8
Replace the blower motor control module. Refer to Blower Motor Resistor Replacement .

Is the replacement complete?
--
Go to HVAC System Check
--

9
Locate and repair an open or a high resistance in CKT 150 between the blower motor control module connector C1 and G202.

Is the repair complete?
--
Go to HVAC System Check
--

10
Disconnect the blower motor relay.
Connect a DMM between the blower motor relay connector terminal A1 and a good ground.
Measure CKT 150 for continuity to ground.
Is the resistance to ground less than the specified value?
0.5ohms
Go to Step 12
Go to Step 11

11
Locate and repair an open or a high resistance in CKT 150 between the blower motor relay connector and G202.

Is the repair complete?
--
Go to HVAC System Check
--

12
Connect a DMM between the blower motor relay connector terminal C2 and a good ground.
Turn the ignition switch to the ON position.
Measure the available voltage at the blower motor relay connector terminal C2.
Is the voltage within the specified values?
10.0 -14.0V
Go to Step 16
Go to Step 13

13
Check the HVAC MiniFuse® #18 for an open circuit.

Is the fuse open?
--
Go to Step 15
Go to Step 14

14
Locate and repair an open or a high resistance in CKT 41 between the blower motor relay connector and the instrument panel electrical center.

Is the repair complete?
--
Go to HVAC System Check
--

15
Locate and repair a short to ground in CKT 41 between the blower motor relay connector and the instrument panel electrical center.

Is the repair complete?
--
Go to HVAC System Check
--

16
Connect a DMM between the blower motor relay connector terminal C1 and a good ground.
Measure the available voltage at the blower motor relay connector terminal C1.
Is the voltage within the specified values?
10.0 -14.0V
Go to Step 20
Go to Step 17

17
Check the BLO MOT MaxiFuse® #49 for an open circuit.

Is the fuse open?
--
Go to Step 19
Go to Step 18

18
Locate and repair an open or a high resistance in CKT 1342.

Is the repair complete?
--
Go to HVAC System Check
--

19
Locate and repair a short to ground in CKT 1342.

Is the repair complete?
--
Go to HVAC System Check
--

20
Reconnect the blower motor control module connectors.
Reconnect the blower motor connector.
Connect a fused jumper wire between the blower motor relay connector terminal C1 and terminal A2.
Turn the blower motor fan switch to the low position.
Does the blower motor operate?
--
Go to Step 21
Go to Step 22

21
Replace the blower motor relay.

Is the replacement complete?
--
Go to HVAC System Check
--

22
Fused jumper wire is still connected between the blower motor relay connector terminal C1 and terminal A2.
Disconnect the HVAC Control Assembly connector C2.
Connect a DMM between the HVAC Control Assembly connector C2 terminal B and a good ground.
Measure the available voltage at the HVAC Control Assembly connector C2 terminal B.
Is the voltage within the specified values?
10.0 -14.0V
Go to Step 24
Go to Step 23

23
Locate and repair an open or a high resistance in CKT 42.

Is the repair complete?
--
Go to HVAC System Check
--

24
Connect the blower motor connector.
Connect the blower motor control module connectors C1 and C2.
Fused jumper wire is still connected between the blower motor relay connector terminal C1 and terminal A2.
Connect a fused jumper wire between terminal B and terminal H of the HVAC Control Assembly connector C2.
Does the blower motor operate?
--
Go to Step 25
Go to Step 26

25
Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Is the replacement complete?
--
Go to HVAC System Check
--

26
Replace the blower motor control module. Refer to Blower Motor and Fan Replacement .

Is the replacement complete?
--
Go to HVAC System Check
--