Whelen PCC8R Issue

[RDT Car 25]

Good Evening everyone. I'm working on wiring up a Whelen PCC8R for my new car. I have it mounted in a piece of wood that will be installed in my trunk. It's mounted next to a PA300 that I modified to run remotely. I went to test the wiring and nada. Keypad lights up, but nothing else. One of the red lights on the keypad did light up briefly when I first tested it but nothing now. I checked the wiring multiple times and no issues. The cable for the keypad is OK as well. I looked at the PC board inside the relay case and no obvious issues. Any help would be appreciated. Thanks.

 

[andrewsim]

Please provide more details on how it is wired. Are all 3 of the small control wires hooked up?

 

[RDT Car 25]

All three control wires are hooked up. Center one to ground and other two to 12v +.

 

[RDT Car 25]

Let me try this again with a few hours of sleep. I wired the relay box as directed in the manual. I tied the 12v ignition and backlighting wires together with the main 12v power leads. They were attached to my 35 amp power supply, along with the black ground lead. The switch panel backlighting lights up, but none of the switches activate. I retraced the wiring several time and found no issues. I am completely at a loss.

 

[RDT Car 25]

I have another question. I just thought of this while at work and can't test out my theory.


Does anyone know of the relay box itself needs to be grounded? The install guide doesn't mention it. I have it mounted to a piece of wood so I can build the wiring harness before I mount it on the car.


That's the only other idea I have other than a equipment defect.


The only other ground connection is an 18 gauge or so wire that's in the same connector as the ignition and backlighting wires.


Thanks.

 

[Torpedo]

Let me try this again with a few hours of sleep. I wired the relay box as directed in the manual. I tied the 12v ignition and backlighting wires together with the main 12v power leads. They were attached to my 35 amp power supply, along with the black ground lead. The switch panel backlighting lights up, but none of the switches activate. I retraced the wiring several time and found no issues. I am completely at a loss.

Power supply. Try it on a battery. Some devices will not tolerate the ripple present in power supplies. Even a battery parallel to the supply will usually smooth the ripple long enough to test things. DT

 

[RDT Car 25]

Power supply. Try it on a battery. Some devices will not tolerate the ripple present in power supplies. Even a battery parallel to the supply will usually smooth the ripple long enough to test things. DT

Thanks DT. I'll try it when I get home. Even though it's a regulated power supply, I didn't think about that. It's worth a shot at this point.

 

[RDT Car 25]

No change with the car battery or grounding the relay box itself. Normally closed side of the outputs has power. I wonder if its the switch panel itself and not the relay box.

 

[ERM]

Power supply. Try it on a battery. Some devices will not tolerate the ripple present in power supplies. Even a battery parallel to the supply will usually smooth the ripple long enough to test things. DT

Ripple on power supplies? Do you know how noisy the electrical system is on a vehicle, especially with the engine running?

 

[Torpedo]

Ripple on power supplies? Do you know how noisy the electrical system is on a vehicle, especially with the engine running?

Yes, very noisy however buffered by a battery. It was a shot in the dark I have seen before. Sorry it wasn't the issue at hand. The ripple I post of is from AC current (which is not present in a noisy or otherwise vehicle) and can confuse the signals created by matrix (b link?) devices. Modern power supplies are cleaner than the one's in the '90s which is when I ran into this issue and corrected it for engineering as they tested sampled timers of an early design digital nature on the test bench. Best of luck with this elusive problem.

 

[twodogs603]

You do have 12v going to the main connection that powers the relays, right? The relays wont work with out something feeding them.

 

[RDT Car 25]

You do have 12v going to the main connection that powers the relays, right? The relays wont work with out something feeding them.

Yes sir.

 

[RDT Car 25]

Well after speaking to Whelen Tech Support, they're stumped as well. Suspicion falls to an issue with the control head itself. So back it goes tomorrow.

 

[RDT Car 25]

Update:


I recevied the new unit Tuesday afternoon. After some trouble shooting, it was the relay box itself. The unit works perfectly now. I'll post some install pics once I get it finished up.