You should check your fuses with a dmm. Short of that, I usually swap Dmd parts to test. But the little sized one in batman is uncommon. Could be Dmd itself, display board, ribbon cables. Hard to say with just this.

You bought the game like this or was gone to " sudden death " some time ago in your possession ?
Check the voltages at the dmd connector to start with something ,,,,,,,

You could try a new ROM but that is not likely to be the problem. Make sure the red stripe on the ribbon cable goes to pin 1. I hope you got a very good price, because the 128x16 DMD's are not readily available. You can buy just the glass, but that is a soldering job left only to the professionals. Your best bet is to get the PINLED version which does not use the high voltage section of the power supply since it is LED. International shipping, but it is about the only option. We did a TMNT this way and it looked fantastic.

http://www.pinled.de/pinledeng/html/produkte.php

Small 128x16 DMD, connector J2:

J2 pin 1: +5 volts
J2 pin 2: Ground (logic)
J2 pin 3: KEY
J2 pin 4: +12 volts
J2 pin 5: +68 volts
J2 pin 6: -98 volts
J2 pin 7: -110 volts
J2 pin 8: Ground (high voltage)
J2 pin 9: Ground (high voltage)

Small DMD Problems and Fixes.
A very common problem on the small 16x132 displays (as used on five games, Checkpoint to Batman) is a failed R95 resistor. It is very common for this 33k, 1/2 watt resistor to go out of spec, or even open. This will cause the display to look garbled (see picture). Often the display itself is fine; it's just this resistor that needs to be replaced.

The display on "Mutant Ninja Turtles" with a bad R95 resistor.

The same display after R95 is replaced.

When replacing the resistor, it is best to just cut the old R95 resistor out, closest to the resistor itself. Then solder the new resistor to the old "legs". It is very easy to tear the traces when removing the old R95 lead. This technique will prevent that.

R95 is replaced here.

If after replacing R95 the display is still garbled, check for torn traces. The top lead of R95 connects to the top lead of R94. The bottom lead of R95 connects to the top lead of transistor Q2. If continuity is not detected between these points, replacing R95 won't change anything until the torn trace(s) are repaired.

Vertical Lines in the Small DMD.
Another problem seen on the small DE dot matrix display is vertical lines, which completely distort the images behind it.

The vertical line problem in small DMD displays.

In this case, this problem was fixed by replacing the display. Always replace R95 first on the display, and see if that fixes the problem. If it does not, the next step is to try the display in another small DMD DataEast game, to verify it is actually the display at fault. In this case it was the display at fault, and the fix was to buy a new display (though a display driver chip is probably at fault, the easy, but expensive fix, was to replace the display).

Testing the Small Dot Matrix Display Glass.
Use this technique to test a new or used small (128x16) dot matrix score glass. This technique uses an existing small dot matrix display panel to test a loose dot matrix score glass. Here is the procedure:
Turn the game off.
Lower the display panel on the game.
Connect a (black) alligator jumper wire from either lead of capacitor C29 (near U15) on the back of the display glass' circuit board.
Connect the other lead of the (black) alligator jumper wire to one of the row pins on the dot matrix glass. This connector puts -100 volts DC on the row the jumper is connected to. NOTE: there are two sets of row pins, on each side of the display glass. Each set corresponds to that half of the display glass.
Connect a (red) alligator jumper to the banded side (cathode) of CR2 on the dot matrix display board (this is a connection to +68 volts DC).
Put a 33k ohm 1/2 watt resistor in the free lead of the red alligator clip.
Turn the game on.
Touch the free end of the resistor (which is connected to the red alligator lead) to one column lead on the display glass. Note the column must be on the same half of the glass as the row connected!
The dot which intersects the row and column should glow.
This test can also be performed for new dot matrix glasses that have not been installed, using the existing dot matrix controller board. For a quick column test, just run the free resistor lead along the column pins. Remember only one side of the row (the side with the row jumper) will work at a time. This was discussed in DataEast's service bulletin number 76.

A quick approach if you have data on the ribbon cable is :
1. verify the eprom data
2. change the Z 80,,,,,,, to some boards is socketed
3. change the RAM

If still nothing you will need a scope and some digital electronics knowledge

Can you type out all the voltages for us?

So 68 volts is reading what voltage at pin 5?

Seen many DE games with 0 volts for 68 volts. DMD needs that voltage.

CPU can be bad. Do you have one to swap with ?

I have had a strange issues once in the past a display board which works fine in Hook does not work in a Batman ,,, so take your display from Batman and test into the pinball of your friend which has borrowed you the 128x16 test display ,,,,,,,,or there is the " Twilight Zone "

We are having issues with the dmd resetting during gameplay too. After installing a new LED display, a new DMD display rom, new ribbon cables, and a new power supply the dmd still resets randomly during gameplay and/or during the Star Trek preview, except it still keeps score.

From Clay's Repair Guide: This problem occurs because the +12 volts needed for the dot matrix display is generated by the 18 volt lamp matrix bridge and the capacitor / fuse bolted inside the back box (through connector CN5 on the power supply). The 12 volts generated by the power supply board (for the sound board which comes from connector CN6), does not provide this voltage to the dot matrix display. Hence, the power supply could be working perfectly, and this problem could still exist.

This sounds and looks exactly like what is happening. We have looked at this in Clay's Repair Guide and are doing all the reset suggestions, (i.e. replace diodes, bridge rectifiers, etc....)

If this doesn't work, then possibly installing a new CPU board, or sending it off for repair, might resolve this issue?

Was it a known working DMD?

The 18 volts RIVERKEEPER mentioned is worth testing.