I have problem with my tas system. Anytime I put the avionics switch on, the 3amps tas circuit breaker trips off. I have checked for short circuit in the system and is OK. During my troubleshooting I realised that when I disconnect the p1 connector from the tas processor the circuit breaker does not trip off. When I connect the p1 connector and switched the avionics switch on it goes off again.
What could be the problem?
It would be helpful if you would tell us what type of aeroplane, and what category (certified? experimental? uiltralight? glider?). Even more interesting, what make and model of Collision Avoidance (as I think it is properly called) ?
Does the Collision Avoidance System have its own on/off switch? I suppose not, because you don’t mention one. But if there is, have you tried powering on the Avionics master with the CAS switched off?
And also: how long has the system been installed? Has there been a time when it worked correctly?
It seems to be in your TAS computer. Though it could also be in the P1 plug, that the positive wire shorts against a pin which is ground on the TAS computer, when you hook up the connector.
Does the power lead to the TAS also feed power to the encoder, if fitted? Might be that circuit or unit that is suspect.
It is installed on diamond da42 NG with Garmin g1000. The TAS is powered by switching avionics switch.
Option list for that aircraft shows a Avidyne TAS610.
Disconnecting P1 simply removes power from the TAS. Pins 1&2 supply power to the unit . Pins 3&4 are ground.
If they are secure I would swap the breaker as the first step.
If it still trips then it is doing it’s job and you have no option but to get the box checked.
I’m sure you didn’t but whatever you do don’t try disconnecting the antenna cables as that will trash the unit.
SteveN wrote:
If they are secure I would swap the breaker as the first step.
Replacing parts without a good reason is a common practiced by many, it is also an expensive way of troubleshooting. I hate that to be honest, and highly doubt it will be the circuit breaker tripping at a much lower current rating. The wiring itself isn’t causing a short circuit. So either loose / poor wiring at P1, shorting out trough the TAS processor (for example, the positive wire also touching the connector shell wouldn’t cause a problem as long as the connector is not engaged (no circuit)). Or something wrong with the processor.
SteveN wrote:
I’m sure you didn’t but whatever you do don’t try disconnecting the antenna cables as that will trash the unit.
Good comment!
Replacing parts without a good reason is a common practiced by many, it is also an expensive way of troubleshooting
I totally agree except that sometimes
What do you mean by airport politics? That you cannot do whatever you want in your hangar? … Or hangars sometimes look like shops when it’s warm enough … Do they not allow working on your airplane?
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