One woulod hope that the dealer would do this as part of some service, but my expoerience is they sometimes "forget".

The VSA oil needs to be changed periodically - the modulator is very expensive, brake fluid cheap. I plan to do it every 15k, when I am doing the ATF. I recommend brake fluid flushes every 15k, which I do myself using a MityVac.

Here is how to do the modulator:

1) Locate the VSA modulator - it is right in front of the windshield washer reservoir filler cap (blue) on the left side of the engine compartment when you pop the hood. It has lots of linesw running in and out of it.
2) Locate the cover plate - it is a small rectangle held on with two 5 mm bolts - remove them and put in a safe place
3) Remove the contents under the cover - there is a bracket and a filter - do not get any fluid on the paint! - cover the reservoir with a clean paper towel or shop rag.
4) Clean the filter if dirty with a solvent and let air dry away from airborne debris such as leaves, dust, etc.
5) Remove the old fluid - I use a clean kitchen baster to remove it - one can use an oil pump as long as it is super clean
6) Discard the old fluid appropriately
7) Refill the reservoir with Honda brake fluid.
8) Carefully replace the filter and bracket and cover.
9) Start the engine and drive until you hear the brake modulator do its cycle "hum".

You are done!

 

Another good one for our 'How To' library. I bet most service departments never think of changing it.

 

Is that unit really considered the VSA modulator? I thought it was the ABS modulator. I know VSA uses ABS, but do they really call it that?

 

They really do call it the VSA Modulator (CLS Helms 19-176). The "VSA Fluid Replacement" is described on page 19-177 (CLS Helms manual). The VSA Modulators in the -S models does the work of ABS/TCS and includes the additional reservoir (not shown for the ABS/TCS unit).

There are people who upgrade their brake fluid to DOT-4 and forget that there is DOT-3 “Honda fluid” in the VSA Modulator reservoir.

The ABS/TCS page (19-92 in the CLS Helms) shows a different unit without a reservoir and/or cap (and there are no instructions on bleeding any fluid in the unit). (Same # of input and output lines as the “VSA Modulator”)