'00 Regal LS No Climate Control AT ALL!!!!

Hello,
I have a 2000 Regal LS with the manual dual climate control unit and it has decided to completely stop functioning. Nothing on it works at all, no fan, no heat, no ac, no rear defrost, nothing. After the car runs for a long enough period of time, residual heat will come out of the vents but without the blower running.
When this problem started, the blower would run when it wanted to, one time you would get in the car and nothing, next time you get in the blower is running 100 percent, that has stopped completely now.
I have read about other peoples problems but have not heard anyone having this one.
Yes I checked fuses, inspected wiring, found no problems. I have had ignition switch issues in the past with this car but have not been having that issue for quite a while.
Any ideas would be greatly appreciated.

Yes, it can be related to the ignition switch. Cause in GM, it has a separate contact for HVAC system and ignition system in the ignition switch.

Try to play with the ignition switch (cycle ON and OFF). See if vent operate while you start the engine. Add contact cleaner where you put the key in.

Check if you have voltage at HVAC fuse when contact is ON. You can remove the fuse while testing.

Just to be sure check the 12 volts going into the climate control unit at the respective fuse socket. Although it could be an ignition switch issue it doesn't sound like it. More like the climate control head unit.

Also, what does the blower do in fan speed position 5 - high?

The fan in position 5 is in the High position, but it does not do anything anymore, there is no response to any movement of any knob or slide or button on the unit. I will be checking out the voltage at the fuse this afternoon and will let you know what I find. Thanks for the help, gotta love this forum!!

OK, so I checked voltage at the fuse and I am only getting 5-6 volts across the fuse, BUT, with the fuse removed, the blower comes on when the speed selector is in the 5 position and it comes on high speed. I do NOT understand that at all?????? So I am surmising that I have an issue in the ignition switch with the lack of voltage at the fuse, would that be correct? Is there something else it could be?

Yes, it's the ignition switch. Cause you should have 12V. You can try remove the fuse and plug a 12V wire to the fuse contact to see if it works. You can also just connect a wire to another 12V fuse w/o remove it. You can connect it to the contacts at top of the fuse.

The reason why the blower start when you remove the fuse, is maybe because at 5° position, the blower uses another HVAC fuse. You should have 2 HVAC fuses.

I've the schematic of your system if you want it. I just realize that.

Some more detailed troubleshooting may help. What wiring diagrams are you using? The voltage drop is either across the ignition switch contact used or a component loading the circuit down.

Is your cruise control working? The same 12 volts from the ignition switch contact used feeds at least three other fuses. Cruise (10 amp) and HVAC (10 amp) for sure. So check the cruise control operation.

Normally with a bad ignition switch you get other symptoms or other accessories not working properly.

I get it from my GM manual. This schematic is for Regal 98 thru 2002.
It's similar as Grand prix 98-99 and Monte Carlo 98-99. Maybe other years too.

Link to copyrighted material removed by Moderator

Second page:

Link to copyrighted material removed by Moderator

The second page cover also cooling engine system components.

Like you see, the ignition switch for HVAC contact is directly connected to fuse no 4.
And there's another fuse connected directly to battery. Plus underhood fuses.

The 2 pages follow. Wire with same number connect themselves through pages.

I suggest also to measure many other fuse voltages in run position (not just HVAC) to compare. You'll get a better idea where can be the problem.

I get it from my GM manual. This schematic is for Regal 98 thru 2002.
It's similar as Grand prix 98-99 and Monte Carlo 98-99. Maybe other years too.

My question in Post #7 was directed to the OP (Original Poster) who has the problem not you. And please do not post images of copyrighted material from a factory service manual.

But keep up giving the good advice.

I do not have a wiring diagram to work with unfortunately. I am shooting blind here. I do know that the blower works only occasionally now, it does not come on everytime, and that the a/c, rear defrost, heater do not work at all. I have had the flashing dash lights issue that is so commonly reported, as well as the key being locked in the ignition, but this are not a constant problem, so I am guessing that the ignition switch needs to be replaced regardless of the hvac issue and I am going to try to get that done this weekend and see if it has any affect on the hvac issue.

Before replacing the ignition cylinder, try what I suggest. When you turn on, you have only 5V on HVAC fuse input. Connect a wire from 12V aux output to that fuse. Or from another fuse output. If it works, the problem is the igntion switch.

If not, it may be a short in the HVAC circuit. Measure also the current in the circuit. Remove the fuse for testing.

With the info given in post #10, I would say a new ignition switch/harness assembly (not ignition cylinder) is going to fix your problem. The issues regarding the ignition switch/harness are due to weak/arcing connectors, so they can be totally random and go weeks working fine, then suddenly not at all.

I forgot to add a Welcome to AF Timchelle!

I have a 2000 Buick Regal LSE. This problem used to be intermittent but has gotten to the point that I never see a "normal" operating state from my HVAC controller unit. The problem is that when I turn my car on the controller usually comes up completely blank except the 4 red lights on the passenger side climate control. The heater then comes on at high fan.
I took it to local Mechanic. He fixed a vacuum leak and it worked for 2 days. I took it back and he said that the HVAC controller was bad. So, I bought a refurb and installed it. It acted the same as the original... He suggested I take it to a GM dealer.
I took it to a GM shop and they pronounced the refurb unit bad... I asked them if the actuators/ vent doors were working and they indicated that they were-all that from a diagnostic test. So I replaced the control unit with one from a more reliable source and got the same erratic performance.
So, I might take it back to the GM shop, unless the forum has some ideas.
Voltage at the fuse for the HVAC unit is about 12. I can pull the fuse, replace it and sometimes the unit will reset and work for a minute or two.
Could it be the PCM or an actuator (which one?) Maybe the ignition switch?

Only the high speed was working on my 2000 buick regal blower motor. So I changed the resistor block, nothing. Next I changed the climate control and again nothing. No more parts changing, time to take a really close look. About the same time my cruise went out and my rear window defogger was intermittent. So I checked the wiring diagram (Luckily I picked up a repair manual CD on ebay years ago) and noticed the fuses for all 3 were feed by the same wire from the ignition switch and was only on in the run position. The fuses are next to each other so I took out the cruise fuse and measured voltage on its hot side. It was about 11 but dropped to 0 when I turned on any blower motor speed except high. I picked up a fused jumper wire, took out the 2A radio fuse and the 10A cruise fuse and jumped the hot side of the radio fuse to the hot side of the cruise fuse to feed power to the low speed blower motor and the rear window defogger and everything worked. I checked the cruise by putting that fuse back in taking out the fuse next to it to jump power there, took a ride and now the cruise also worked. Not wanting to change the ignition switch, I picked up some mini fuse taps so I could put in a jumper wire from the hot sides of the 2A radio fuse to the 20A low blower fuse and now everything works, except the blower, cruise and a/c now get power when the ignition switch is also in the acccessory position and after the car is turned off until the driver door is opened but I can turn them off and don't sit in the car with those on anyway. I think the windshield washer power was also included with that problem but no problems now. So if you tried everything else, check the voltage at the cruise fuse when you turn the blower on and good luck. Or better yet, check the voltage before you change any parts.

@ Jake Richmond - what was the end result/fix to your issue? My 2000 SLE recently started having the same exact symptoms. My intuition is leading towards another ignition switch. I already replaced it once about 7-8 years ago. I would be interested in hearing what the actual issue was with your vehicle.

Others - any thoughts/inputs?



I have a 2000 Buick Regal LSE. This problem used to be intermittent but has gotten to the point that I never see a "normal" operating state from my HVAC controller unit. The problem is that when I turn my car on the controller usually comes up completely blank except the 4 red lights on the passenger side climate control. The heater then comes on at high fan.
I took it to local Mechanic. He fixed a vacuum leak and it worked for 2 days. I took it back and he said that the HVAC controller was bad. So, I bought a refurb and installed it. It acted the same as the original... He suggested I take it to a GM dealer.
I took it to a GM shop and they pronounced the refurb unit bad... I asked them if the actuators/ vent doors were working and they indicated that they were-all that from a diagnostic test. So I replaced the control unit with one from a more reliable source and got the same erratic performance.
So, I might take it back to the GM shop, unless the forum has some ideas.
Voltage at the fuse for the HVAC unit is about 12. I can pull the fuse, replace it and sometimes the unit will reset and work for a minute or two.
Could it be the PCM or an actuator (which one?) Maybe the ignition switch?

Update: Replacing my ignition switch fixed my issue. Cruise Control now works and as well as the dual HVAC controls. Thanks


@ Jake Richmond - what was the end result/fix to your issue? My 2000 SLE recently started having the same exact symptoms. My intuition is leading towards another ignition switch. I already replaced it once about 7-8 years ago. I would be interested in hearing what the actual issue was with your vehicle.

Others - any thoughts/inputs?