autostaretx
Erratic Member
In theory, it's a Yellow wire
--dick
--dick
Weak power-lock signal despite replacing key fob batteries. Receiver location?
- Thread starter misterbond10
- Start date
Nautamaran
2004 140” HRC 2500 (Crewed)
Yup... shown on page 8W-39-12, but in my case Pin 1 has a black wire.
If you pull the harness down a little from above the head liner the antenna ends there, and can be pulled back and extracted from the bundle down to the base of the pillar. From there I tucked it in between the plastic dash and the black rubber molding at the windshield. Vanishes from view with the speaker grate back in place.
Went for a walk, hitting the Unlock button as I went... Got to 200 feet away (last image) before signal lamps stopped blinking their reply.
So I’m VERY happy!
-dave
Attachments
Last edited:
It may be a tuned length, but I doubt it.
If you re-route the wire out to where it is accessible, then tacking on some extra length using a wire nut is easy. If it works, make it more permanent. If it doesn't improve, remove it.
vic
So I soldier a 18 ga wire to the end of this antenna, then ran the wire across the top of windshield and down the passenger side. In testing walking up to the van it gave me about 10’ more range. It also seems to be a bit more consistent. My verdict on this mod is it helps a little, but still no where nearly as good as my other cars remotes.
autostaretx
Erratic Member
In the US/Canada, the remote key (and tire pressure system) uses 315 MHz (megaHertz)
The full-wavelength for that is 37.5 inches, and a quarter wavelength is 9.375 inches.
So the "best" exposed antenna length would be 9.375 inches
The best arrangement for an antenna is to stand vertically above a ground plane (kind'a like your external radio antenna).
The wire feeding the 9.375 inch antenna should be coax (active conductor shielded by a grounded coating), or the feed length will be counted into the 9.375.
--dick
p.s. i thought that a half- (18.75) or full-wavelength (37.5) wire might do better, but the references i'm hitting all vote for the quarter-wave. Then i found another reference that likes the half-wave, plus another that votes for 5/8ths wave (23.43 inches).
p.p.s. you may also find that experimenting at the edge of your current range but reorienting the key fob may make a major difference. Try "pointing" at the Sprinter with the back of the fob, the side-edge of the fob, the top edge of the fob, and with the key extended. That will be reorienting your transmitting anternna (and who know where/how it "points" inside the plastic?. Also try NOT surrounding the fob with your hand (i.e. "pinch it from the top" kind'a thing)
p.p.p.s. typical reference: http://www.hoperf.com/upload/rf/antennas_module.pdf
The full-wavelength for that is 37.5 inches, and a quarter wavelength is 9.375 inches.
So the "best" exposed antenna length would be 9.375 inches
The best arrangement for an antenna is to stand vertically above a ground plane (kind'a like your external radio antenna).
The wire feeding the 9.375 inch antenna should be coax (active conductor shielded by a grounded coating), or the feed length will be counted into the 9.375.
--dick
p.s. i thought that a half- (18.75) or full-wavelength (37.5) wire might do better, but the references i'm hitting all vote for the quarter-wave. Then i found another reference that likes the half-wave, plus another that votes for 5/8ths wave (23.43 inches).
p.p.s. you may also find that experimenting at the edge of your current range but reorienting the key fob may make a major difference. Try "pointing" at the Sprinter with the back of the fob, the side-edge of the fob, the top edge of the fob, and with the key extended. That will be reorienting your transmitting anternna (and who know where/how it "points" inside the plastic?. Also try NOT surrounding the fob with your hand (i.e. "pinch it from the top" kind'a thing)
p.p.p.s. typical reference: http://www.hoperf.com/upload/rf/antennas_module.pdf
Last edited: