Hornby A4 TTS chip problem

[mikeg]

I have been trying to install a TTS chip in a Hornby A4 which runs well on DC but with the chip installed I get a short. With the chip out and the blanking plate there’s a short on the rear drivers and also between the third pair of pins on the PCB that the chip fits into! Has anyone had a similar problem or any ideas what maybe causing the problem?

 

Thanks for any help Mike 

 

[RAF96]

Unscrew the socket and look at the underside for solder bridging. Usually with the blanking plate in any error here does not matter but with a chip installed isolation between pins is essential.

[mikeg]

RAF9, thank for your reply, there was a very fine trace between two of the pins once cleared the sound came on but as soon as I pressed the speed step button it went off.

I switched the sound off and the loco started to move but was jerky, when I turned the speed up to step 7 the loco stopped and the chip gave a small puff of smoke and died!

I think this maybe why the loco was reduced in price as it will not run on DCC but runs very smoothly on DC.

 

Regards Mike

[RAF96]

Contact Hornby and see if they will replace it under their no quibble 1 year warranty. Lost your receipt probably ...

[mikeg]

As it’s not my chip and from what my friend has told me it’s about 18 months old, but it had been used ok in a diesel to test it when originally bought. He’s not worried about it and has already disposed of it.

 

thanks for the suggestion, mike