colecovision help

[jc78_2005]

ok , i now have 2 colecovision consoles that with a prob i assume is power related. on both i have already taking apart the power switch cleaned and resoldered. power supply is for sure good to go. and also checked where the ac inputs connect to the board. ok ,one of them always goes to black screen and tone.the other most of the time comes up to garbled lettering with or without a cart it does change with a cart in however so im not thinking its the cart edge connector , i assume it is a 4116 issue, is there a way to narrow this down to which one it is ? or should i just replace them all on both? i read , that u15 is common with the garbled lettering but , on one of them it has been clearly replaced already? soo any help is greatly appreciated it!

[VectorGamer]

The black screen and tone I have seen most recently with carts I purchased through auction. I simply clean the contacts and surrounding area with a Q-Tip and rubbing alcohol and it fixes it. It sounds to me like you would've already done this based on the advanced troubleshooting you have done with the power switch.

 

I have the same problems with the garbled lettering. I can rule out the power pack because I have two of them and it makes no difference. I still cannot pinpoint if it is the power switch or the actual connector for the power plug. I'm thinking it is the former but I have not come across any documentation of one having problems with the connector itself and the resulting instructions for replacement. The reason I suspect the connector is based on the fact that if I reinsert the power plug the problem goes away. This also fixes the problem I have with rogue sprites that appear in the game.