2003 Sonata Keyless Entry

First off, the Hyundai remotes have about half the range of the other remotes. Second, many, many things can interfere with proper remote operation.

That being said, it's possible you have a problem with your remote itself. If the battery tests to 3V, it should be okay. If you think you have a problem with your remote, ask the dealer to have a look at it on your next trip in.

Thanks! You know, I didn't think about the remote... I was thinking it was the receiver except that the trunk and open buttons work fine. John D.

Why is that. My Sonata remote has longer range (100' at least) than my Chrysler minivan. My Chevy truck don't use no steenkin' remote controls!

Matt

Wow! I've never seen a Hyundai remote even approach 100 feet before. It's usually about 50 feet, tops, with an advertised range of 25 feet. Most other manufacturers I've seen advertise the 50 foot range.

Obviously, the more powerful the transmitter, the better the range. Some transmitters use two 3V batteries instead of one. I haven't opened one of the newer-model remotes, so I don't know whether that's the case with them.

If you're in an area with strong rf signals, then you're more prone to interference. I saw some poor technician try to diagnose a customer's intermittently inoperative keyless entry over about three or four service visits until he happend upon some papers under one of the seats with a television station's letterhead. Turns out the problem only ever occurred at work. Whaddaya know? I've heard some stories that there are areas in southern Maryland where car remotes won't work for a few days. I'd suspect this may be related to military testing. There were verified news reports of people's garage door openers not working in Frederick, MD due to military operations at Fort Detrick. Bottom line, these frequencies were intended for military use, and these devices are simply allowed to borrow the frequency when the military is not using it. The devices just operate at a low enough power that they aren't strong enough to interfere with the military uses of the frequency.

I get about 600' LOS range with my 01 Santa Fe's (annoying 2 button remote). The 03's gets about 100' (more annoying 3 button remote).

Must be a little lithium cell? My Explorer used a 12v lighter battery, they lasted years. One of my 01's has started to fade a bit. Should I (can I) replace the battery or get a new fob?

What frequency do the key fobs use?

I've got all the ISM 915/2.4/5.3/5.8 spectrum in use here. Doesn't appear to be any of those.

JS

JS writes: Must be a little lithium cell? My Explorer used a 12v lighter battery, they lasted years. One of my 01's has started to fade a bit. Should I (can I) replace the battery or get a new fob?"

If it's fading, try a new battery. There's a quite large chance that's all the issue is.

Can't tell you what the specific frequency range is. I never particularly cared what the range was, so I never tried to hunt it up.

Probably not the fob... I found out yesterday that the door lock button on the driver's arm rest is also intermittent... It's a warranty problem! John D.