Repair of a Celestron Evolution mount, short circuit on the circuit board

3.427 / 5.000
Product Description

Problem:
With a Celestron Evolution mount (>3 years old), nothing happened when turned on. Neither the handheld controller nor the batteries were charging (indicated by the red LED on the side), nor was there any other reaction.
The customer described that after the last time the mount was turned on, it rotated several times on its own axis, probably tearing off and breaking the charging cable connector.
Tests of the handheld controller on another Celestron mount at our company showed that it worked flawlessly. Even connecting a new charging cable did not result in any reaction from the mount.
During and after opening the mount, traces of corrosion were noticed on the screws, connectors, and circuit board. A slight "electronic" smell of smoke increasingly indicated that a short circuit must have occurred on the circuit board.

Solution:
Since the mount has a four-digit purchase price and Celestron offers individual parts (such as the circuit board), replacing the circuit board was worthwhile. The circuit board we ordered came with a so-called retrofit package.
The circuit board of the several-year-old mount was the Evo Rev F version (stands for Evolution Revision Version F), while the new board was the Evo Rev J type.
This meant that not all connectors were compatible, and some tinkering was required to reconnect the circuit board.
The retrofit package includes: a new circuit board (here, Type J), ​​a new internal power cable, as well as connectors and cable clamps.
Since we also suspected that the internal power cable was also affected, this worked out well.

Step 1:
Removing the circuit board.
To do this, carefully unplug all connectors connected to the circuit board and loosen the four metal screws.
Tip: If you want to avoid spending hours poring over circuit diagrams after installing the new circuit board, take a photo before removing the board and color-code the identical connectors so you'll know immediately where each cable goes! This will also prevent unnecessary troubleshooting later ;-)

Step 2:
Tip: Leave the new circuit board uninstalled for the following steps. This will provide more space for handling and prevent possible contact damage to the new circuit board.

Now, remove the old internal power cable from the charging cable connector. This is easiest if you first loosen the two screws on the left and right of the console on the opposite side.

Now, install the new cable and screw the console back on.

Step 3:
Now, the old battery connector needs to be reconfigured. The new connector has two wires instead of the previous four. The connector is easily identifiable by the two red and two black wires coming into it. Bravely cut all four cables immediately after the connector. Now strip the insulation from the cable (approximately 5 mm) and twist the two free red cables together and clamp them (in the cable clamps included in the package) into the cable clamp (see photo). Do the same with the two black cables. For safety's sake, we tied the two twisted cables together with insulating tape.

Then plug the cable connections, now reduced from four to two, into the connector plug.

ATTENTION: The flat side faces the connector window!