Simpson 260-6XLP Protection Relay Always Tripped

[Ultron81]

I recently picked up a Simpson 260-6XLP VOM for a great price. Problem is, as soon as I connect the internal 9V battery, the protection relay trips and disconnects the COM terminal from the rest of the meter. When I hit the RESET button, it will not reset. The reset button latches the relay contact in place and closes the circuit, and when the relay is energized, this disconnects the contacts and keeps them open.

According to the manual, it should only trip when the input to the protection circuit is 4 to 5 times above the meter movement range. But in my case, the protection relay is on and won't reset even without any input applied to the meter.

I removed R44 to try and eliminate any input to the circuit. The circuit still energizes the relay and I can't reset it. I tested all the diodes in the protection circuit and they seem OK (they are 1N100 germanium diodes, except for the diode across the relay coil). The transistors test OK as well, and I even replaced them with NTE equivalent parts (NTE123AP for the NPNs, and NTE159 for the PNP).

Running out of ideas here, any help would be appreciated!

I attached schematics and a theory manual, thought the manual is not for my specific model, it does give somewhat of a description of the protection circuit. The 6XLP includes an extra NPN to drive the relay coil.

[floobydust]

You've replaced most of the parts, so it's a bit of a puzzle.
I would suspect the transistors because they all turn on to activate the relay. Not much else can cause the circuit to trip.
Note the wonky pinouts, in case that got messed up:
NTE159 PNP has Japanese JEITA pinout ECB.
NTE123AP NPN has American JEDEC pinout EBC.

Check capacitor C5 1uF is not open.
When there is 9V power and the relay is on, measure some voltages on the transistors, C5 etc. Pressing the RESET button should make the relay click assuming the circuit is stuck on.