W126 battery hold downs and Auxiliary fan resistor

When I restored the battery tray on my 560SEL, I noticed the W126 battery hold downs were missing.   While the battery on the W126 sits quite snugly between the inner and outer firewalls, the hold downs are still important.   On a serious bump the battery could short out against the bonnet for example.

These hold downs are the same as on the W123 and other models.   I ordered a new one, thinking that at least having one in place would start, and I would look for a cheaper used one later.   Turns out I needn’t’ have bothered as I found the original hold downs under the tool kit.   I imagine a lazy battery installer didn’t fit them.   Not sure why, as it takes all of two minutes.

When installing the W126 battery hold downs, its easiest to move the washer fluid tank.   Its not held down and there is enough slack in the connections to get it out of the way.

Next job was fitting the fan resistor.   On the W126, the fan can run at low or high speed.   The resistor allows the low speed running.   Low speed running is triggered by refrigerant pressure, so is important for the good working of the A/C system.   While it is buried away on left hand drive cars, on RHD cars its easily accessible behind the left headlight.   Over time, these fail and and were broken on both my 560s.   It is easy to test using a multi-meter and checking for the correct resistance.

I had previously checked this when replacing the auxiliary fan, but it took a while for my new resistor to show up.

I haven’t had a chance to test it yet, as there is also the possibility of a bad relay too.   That is reasonably unlikely and I am pretty confident when I test the fan, it will now work on low speed.