Liberty CRD Diesel '06: Interference with 2m radio transmissions

Fuel injectors are the most likely source of the noise.

First, use a direct connection to the battery terminals. Second, twist the connecting wires 2 or 3 twists per foot from the battery to your radio. Third, get a GOOD chassis ground connection for the radio.

If noise persists talk with the CRD service techs regarding slightly slowing down the rise time of the fuel injectors or adding a suppression diode across the fuel injector coils [it is unlikely you will get any support in this area, but worth a try]

If you contact DC, they might send you the booklet on installing a transmitter into the vehicle. They get very specific on where the power and grounds can be run as well as the antenna wire.

On GM's for instance, you have to have a 10 ga. dedicated fused power and ground line to the battery run far away from any vehicle harnesses to avoid voiding the vehicle warranty. Transmitters can interfere with things like the ABS and transmission modules, like some TJ's will go into neutral when the transmitter is keyed up, and any other electronic part.

Here is a link to GM's instructions, I haven't found any online for Jeeps:

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

Thank you for your on-topic reply!

I do have the equivalent for a 2006 Charger Police Edition, which may be downloaded from the very last link at

andwill look for a similar "outfitter's guide" for the Liberty.

Excellent advice. I would add: fuse both hot & ground for good measure at the battery ends of the connections. You could also loop the power cord a couple of times and put a ferrite bead on the power leads.

Always run heavier wire than you think you'll need. It reduces loss and someday you might want to put out more wattage.

If it's a temporary set-up, use one of those gel-cell booster batteried to power your radio.

73s!

Hi...

With all due respect, don't even think about fusing ground.

Take care.

Ken

Great! Now comes the interminably long thread where everyone argues this Old Rule once again -- without anyone changing their mind -- and with each post starting "With all due respect ..." containing little.

*plonk* the thread

Fusing the ground is recommended and required to do it properly on a GM. If the vehicle loses it's body or engine ground strap connection for any reason (like corrosion for one) the starter or alternator or body/lights, etc. can use the radio as a ground. This usually lets the smoke out of the unit big time.

I have installed hundreds of transmitters in one contract I had and when they came back in for repairs over the years, on about 98% of power short issues either vehicle related or transmitter system related had the negative fuse blown before the positive one. There were lots of cases of blown fuses due to ratty vehicle grounds also.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)

Well, I have a '99 TJ with a 40 watt police radio wired from the battery. Noooo problems in 2 years. Automatic, air, GPS etc also.

When I transmit the GPS loses it's location however.