Information on connections for a 20-3126 Auxiliary water tender to a 20-3365-1 J

Guess what I finally found?  Posted for future reference even though very sketchy.  When I get into it, I will post additional details as they unfold.  If anyone has additional details, please post.

My advice- know the rules. By rules, I mean know that taking an older PS1 tender, means it has PS1 1.5V incandescent backup light and a PS1 electrocoupler.

PS2 and PS3 use a different coupler compatible with the voltage of PS2 and 3 and is completely incompatible with PS1 couplers. Good way to fry the coupler MOSFET or worse.

Further, PS2 uses 6V incandescent bulbs and PS3 is LED. Either way, highly likely that original 1.5V grain of wheat backup light- that gets blown.

And that's assuming the 4 pin connector arrangement pinout even lines up.

There is real risk of damage to a PS2 or PS3 tender electronics (nothing like a $200 mistake) when connecting one of these PS1 aux tenders.

Thanks Vernon for verifying that suspicion.  I was hoping to find the product page on the MTH web site and did not have much luck with several searches.  Looks like this will be eye candy and I will probably add my own LED lighting to it as a stand alone unit with no tender connection. 

You have a PS-1 Aux tender and that early one comes with a harness for the engine tender since the early J and Y-6 did not have one.

Yes there are different configurations on the harness too so you really need to ring out the PS-2 J external harness. Then match it to the New Aux tender.  You will need to put in a 6V bulb and PS-2 coupler also.

Some engine version only power the Aux tender light when you move the switch to Aux.  Others will still power both lights just switch coupler operation.  Another version had Aux tender coupler triggered by the Fwd coupler button and you could trigger the tender coupler even with switch on Aux tender.

After you convert it put a label on the bottom to remind you which engine it works with and that it is modifed for PS-2 etc...  G