Fast red LED blinking no blue LED

[shazzy]

Slight problem with my APM board. Once the board has booted up (after the initial flurry of flashing blue and red leds)  my blue led shuts off and I get the red led blinking at around 2Hz. GPS and telemetry don';t seem to be working now.   

Tried flashing new firmware,  an erase,  resets but still no luck.  Is this a hardware issue and what could it be if it is?

[rickp]

Pre-arm check failure?

[shazzy]

I can still arm and start the motors. Won';t pre arm check failure technically stop me arming?

[kilby]

When you arm do you get a steady red led?

[shazzy]

Yup. Arming results in steady red LED but no blue led 

[optiplex]

sounds to me like a hardware issue

did u try to test the apm without gps and telemetry connected ?
try it without anything connected
see if the blue led flashes as there is no gps module

[rickp]

I';d check the cabling to the GPS - make sure its firmly attached and no bent pints etc.

[shazzy]

I';ve taken everything off and tried it again. No luck. I still get the red led blinking at a slow rate but no blue led.

[Dek]

When it happened to me, I found the soldering flux had not been washed off and was bridging the GPS and Telem pins on the rear of the APM. I used a plastic biro pentop to gently clear between each pin and all was well again.

Dek.

[shazzy]

Its wierd, it was working for a month and then just one day it stopped and the blue light wouldnt come on after booting.
Ive got some PCB alcohol stuff which i might use to clean every nook and cranny and see if it helps. Cheers Dek,