RAS conversion question

I just got my RAS/XREAS swapped to springs and real shocks.

Pulled the 50A and 10A fuses under the hood for the "AIR SUS" circuits.

When I start up after being parked for a while, the compressor still runs like it used to trying to inflate the air bags to the "mid" level. I haven't had a chance to pull the kick panel and disconnect the RAS harness that'll kill the flashing "OFF" light, but I'm really confused how the compressor is actually getting power with its fuse pulled out.

Anyone out there had any similar experience?

 

Turns out that what I've been hearing is some other mechanism that I'd assumed was the RAS compressor spinning up from the low parking height to the "mid" setting. I'm still hearing the same sound after removing the RAS compressor and control valves from the vehicle entirely, so the sound was never the RAS to begin with.

Bonus benefit, removing the compressor and valve (and disconnecting/cutting their associated harnesses) does stop the "warning" blink of the RAS lights on the dash from happening after the air bags are gone, no need to hunt down the right harness to pull under the interior kick panel.

 

Sounds like the master cylinder pressurizing the system. Im assuming its a 4th gen?

 

Yes, 2008 Limited V8. Noise is definitely coming from the engine bay, runs for maybe 5-10 seconds on starting up.

After seeing the RAS compressor and where it was located, I'm amazed it managed to run as quietly as it did. Now I'm wondering if I can m somehow manage to put a bigger compressor for a OBA system up into that space, especially since I'd be using a 4-5 gallon pancake tank (or maybe a couple of "hot dog" tanks) bolted up into the spare tire cavity with the spare on a rear-bumper swing out; I'd be able to keep the plumbing pretty compact, with only a long line to have a plug-in point for an inflator hose in the front bumper.

I've never had a vehicle (including a 1st gen and a 2nd gen Tacoma) that made a similar noise, or had a hydraulic pump that sounded like this. I'd have expected the brakes in a 2008 4Runner to be pretty much the same as the system in a 2010 Tacoma.

 

The master cylinder has a the brake booster built into it. When u turn the key on its pressurizing the system. Then turns off. Try price a master cylinder for your runner $$$$

 

Its a stupid design that they share with lexus vehicles too.

 

Makes sense in a way. The limited trim T4R is almost a lexus in a Toyota body as it is.

I would have thought the mechanicals would be more common with Toyota trucks, though.