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For those that would like to delete the Automatic Level Control full time connection to the battery, read: System Is Hot With Key OFF! - it is relatively easy to accomplish.

I dove into my FSM to look at my modified wiring diagram for the specifics.

This mod is performed at the Level Control Sensor mounted over the differential; this is relatively easy to get to and remove - versus removing the front left wheel and other stuff for access to the compressor assembly wiring.

Gain access to the harness from the Level [Ride Height] Sensor over the differential. This mod can be done 'on car', but it is much easier to do when it is sitting on a bench in front of you.

Six wires in this ride height sensor harness and plug:

Pin A - Black: Ground
Pin B - Yellow: Compressor Control
Pin C - Orange/Black: Key OFF HOT (Fuse #27)
Pin D - Red/Black: Key ON HOT (Fuse #12)
Pin E - White: Vent Control
Pin F - Blue: Not Used in our application

The objective is to splice the sensor Orange/Black wire into the sensor Red/Black wire. You are disconnecting the KEY OFF HOT wire - where the sensor sees power all the time - and attaching it to the Key ON HOT wire that is only powered when the Key is in the ON position.

Take the other end of the Orange/Black wire that you cut [leading to the harness plug] and "ISOLATE" it. Basically use some 3M black electrical tape and cover it up and tape it back out of the way; remember, this sucker is HOT all the time. Or get fancier based on your time/talents.

Reinstall the sensor and plug the harnesses together. Your ALC system in total will now only operate when the key is ON.

Pretty simple fix/mod and eliminates a potential source for a dead battery due to leaking ALC air lines and/or connections.
 

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Doug, you can also just swap the wires on "C" and "D"

Only thing about this deal is on hot days the car can get decidedly "tail up" after parking it.
The heat soak up around the shocks or bags greats trapped and the pressures rise.

Gerry
 

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I had this issue on my 88 buick Electra estate wagon. I just unplugged the compressor all together. Idk if this can be done on b-bodies.
 

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I switched the wires in the plug. We'll see how it works.
Swapping the wires does not work. The compressor doesn't start. This is because the controller needs a reset signal, which is provided by the ignition turning off and then on. If the controller gets an always-hot signal, it never resets, and the compressor won't start.

I have to get back underneath the car this weekend and put the wires the way they were.

I had this issue on my 88 buick Electra estate wagon. I just unplugged the compressor all together. Idk if this can be done on b-bodies.
That's fine if you don't want the level control. I like it.
 

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Not sure what to say as mine has been working for years like that.

There were-are different part numbers and change ups for the sensors, maybe it is a matter of some do , some don't.

The only weird thing my car does is, if I have the car with wheels hanging for an extended time with the ign on. It will time out and not work.
After that and I have given up on it, the next time I pay attention to the system it is working fine.
Sorry if I have lead you astray.

Gerry
 

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I think the sensors are the same for the most part. I put a sensor from a 98 park avenue in my 95 RMW. I did have to swap the mounting bracket and the top cover with the arm, but the electronics were the same.
 

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Discussion Starter #9
Follow Up

Nick - your mileage may vary.

My system has been working just like factory 'cept there is no way it will kill the battery wired the way I've wired it as discribed above.

The above worked for me, and I just wanted to pass it on.

Also worth noting - there are not many out there that will tackle this system; i.e, install a better compressor [from Summit] and subsequent mods to make it work and fit 'as factory'. New compressor, added vent valve and solenoid, retaining the system dryer and reservicing it with new dessicant, Key Off Cold......

BTW: the GM ALC compressor is a very cheap piece of junk - similar to the air pumps [junque] on our cars; obviously a 'lowest bidder' item. Hell, just getting new dessicant would be a challenge for most guys..... and you can guess what's next: "what's dessicant?"
 

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I found one of my shocks had a whole in it and was thinking about just simply pulling the fuse to prevent it running all the time until I get a new one. Does anything else run off this fuse?
 

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Not sure what to say as mine has been working for years like that.

There were-are different part numbers and change ups for the sensors, maybe it is a matter of some do , some don't.

The only weird thing my car does is, if I have the car with wheels hanging for an extended time with the ign on. It will time out and not work.
After that and I have given up on it, the next time I pay attention to the system it is working fine.
Sorry if I have lead you astray.

Gerry
I'm paraphrasing the 1994 FSM. Maybe your 1995 is different.
 

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I pulled my fuse (labeled "ELC") a few years ago....it controls nothing else. The compressor seized up and I had no desire to jack with it anymore. I now have a manual fill system....wish I had done that years ago.
 

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I found one of my shocks had a whole in it and was thinking about just simply pulling the fuse to prevent it running all the time until I get a new one. Does anything else run off this fuse?
Pulling the fuse works on TBI cars too. It does not affect anything else.
 

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For those that would like to delete the Automatic Level Control full time connection to the battery, read: System Is Hot With Key OFF! - it is relatively easy to accomplish.

I dove into my FSM to look at my modified wiring diagram for the specifics.

This mod is performed at the Level Control Sensor mounted over the differential; this is relatively easy to get to and remove - versus removing the front left wheel and other stuff for access to the compressor assembly wiring.

Gain access to the harness from the Level [Ride Height] Sensor over the differential. This mod can be done 'on car', but it is much easier to do when it is sitting on a bench in front of you.

Six wires in this ride height sensor harness and plug:

Pin A - Black: Ground
Pin B - Yellow: Compressor Control
Pin C - Orange/Black: Key OFF HOT (Fuse #27)
Pin D - Red/Black: Key ON HOT (Fuse #12)
Pin E - White: Vent Control
Pin F - Blue: Not Used in our application

The objective is to splice the sensor Orange/Black wire into the sensor Red/Black wire. You are disconnecting the KEY OFF HOT wire - where the sensor sees power all the time - and attaching it to the Key ON HOT wire that is only powered when the Key is in the ON position.

Take the other end of the Orange/Black wire that you cut [leading to the harness plug] and "ISOLATE" it. Basically use some 3M black electrical tape and cover it up and tape it back out of the way; remember, this sucker is HOT all the time. Or get fancier based on your time/talents.

Reinstall the sensor and plug the harnesses together. Your ALC system in total will now only operate when the key is ON.

Pretty simple fix/mod and eliminates a potential source for a dead battery due to leaking ALC air lines and/or connections.
Why not just pull fuse 27?

Putting key off power all the time to key on power seems to still give it power all the time?
 

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If you hear the compressor running every now and then when car is off then yes pull number 27. Mine kicked on with a load in every 15 minutes.

If you never hear it kick on to level your batt drain is elsewhere...
mine kicks on for 2-5 minutes EVERYTIME I CYCLE THE KEY from on to off...
car wasn't starting, so everytime I tried the starter and got the clicks of un-starting, the pump would run for another 2-3 minutes and drain the battery.
suffice to say, now my battery is cooooooooooooooooked :)

Thanks, pulling 27 stopped it. I had just hooked up my new battery and the thing started running. Yanked the fuse and it turned off.
 

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I just did this mod. last week by switching the 2 wires at the sensor. Works great. Mine has a slow leak and the pump has been coming on every 15-20 mintues for the last 2 years for a few seconds at a time. Now the pump can't scare me as I walk past the car and my battery won't run dead either. I pulled the fuse last winter to keep it from causing a problem, now I won't have to. I was worried that the bags might get pinched or something with no air in them all winter but it didn't seem to cause a problem. I don't have to worry about that this winter either. Thanks to those that offered this solution!
 

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I left everything in place almost and just removed the fuse for the ride height. I went to cargo coils and monro shocks....they were ok for awhile, but the monro's are worn after 2 years, have been about 6 months....should have went with Bilsteins or coil over shocks...Up front I went with high performance and the same Monro shocks..These aren't as bad for obvious reason, but, that was why I left the items in place, as I just may go back to air rides...we'll see what I can get warranty wise with the Monro's @ pep boyz, if they'll let me jump up to Bilsteins or not and credit me back the Monroscwm3
 
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