Hi i have a hilti te804

any good electronic shop should be able to assist are you sure its the regulator and not needing new brushes as hilti,s are prone for the brushes wearing out

Brushes can be if to short but in most cases there is an autostop inside the brushes to protect the armature, but importanter if look if you have a little powercable break try first to give test under a strain condition giving on the cable with the trigger half in .
If that also have no effect then there can be a loose sliding contact in the electric field or contact to the switch.

replace a burnt out motor

no hammer action

You could have a problem with the armature and or the field.

Brushes dirt in it or regulator fault check also motor running free

To get to the brushes all you need to do is remove the 3 screws on the back handle of the tool. No need to seperate the motor from the gear housing. Pull the back cover off and you have access to the brushes

You can call Hilti @ 800-879-8000 to see if they still carry parts for that model. It is actually a TM7S VSR.

Before buying brushes I would check the commutator segments to see if they are burned. Most times on that model if the brushes were bad then the armature was also bad.

If Hilti no longer carries parts check with Metabo. They manufactured that model for Hilti.

Hilti 800-879-8000

ive checked the hilti website and theres no brushes avaiable
this is a link to the exploded diagram and parts listing
http://www.us.hilti.com/data/techlib/docs/tool_schematics/sfs/UH_240_A.pdf

it looks as though you would need to replace the motor
heres the link for it
http://www.us.hilti.com/holus/modules/prcat/prca_fuse.jsp?RANGE_OID=31634

hope this helps
if it does please vote