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Hollywood,

On that Pioneer system, do the electronic "instruments" work well? I mean does the speedometer on the car match the one on the radio, etc?

What other instruments can you pull up on the radio?

Is it hard to hook whatever makes those instruments work on the radio onto whatever they get that information from on the car?

Thanks!!!!!!!!!!
 

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Discussion Starter · #62 ·
kidcool said:
Hollywood,

On that Pioneer system, do the electronic "instruments" work well? I mean does the speedometer on the car match the one on the radio, etc?

What other instruments can you pull up on the radio?

Is it hard to hook whatever makes those instruments work on the radio onto whatever they get that information from on the car?

Thanks!!!!!!!!!!

well the speedo on the car is different than the one one the radio. the radio one is going off of gps. the cars speedo is off as many people already know.


it can tell side g, f/r g, volts, clock, slope. amd i think one more thing. it also has peak hold.

the hid away unit has to be mounted flat. it will tell you if its not mounted right. all info comes from this little box.
 

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Discussion Starter · #65 ·
the only i have seen so far is the xm traffic display. but that only works in some major cities. there might be more info released that i havent seen.
 

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Does this GPS system require connecting a Vehicle Speed Sensor and a connection to backup lights to the radio? If so, how did you get around that?
 

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Discussion Starter · #67 ·
it doesnt NEED to have the speed sensor. it would be a little more acurate if there were one. and yes i did hook up the reverse light wire up.
 

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just so that everyone knows, the xm radio antenna can be completely hidden under the fiberglass bodywork, no need to put it on an exterior surface. the fibergalss will attenuate the signal but not enough to affect performance. additionally, the terrestrial repeaters that are running in all major cities have excellent signal strength which provides coverage even when you might have a weak sat signal (say in between tall buildings). I personally engineered a custom hidden xm/sirius dbs antenna system that is used by mercedes dealers all over the country. If you have ever seen the stock DBS antenna that comes with the mercedes sirius kit, you know what im talking about; it is horrendoudly ugly. the kit uses the newest mini antennas which are about the size of the pioneer gps antenna. the antenna mounts under the hood and underneath the induction grille which on the driver side is unused and actually sealed underneath.

the exception is on the newer SL series which use the fiberglass trunk lid. on these, the antenna mounts directly underneath the lid behind the inner cover. consequently, all new mercedes (2005 up) that use the fiberglass trunk lid have the sirius antenna hidden as a stock option. on the elise, the antenna can be hidden anywhere under the body where there is no metal obstruction and heat is not an option. ( i would suggest this for gps antenna mounting as well since the windscreen glass attenuates the signal MORE than the fiberglass. the two removable front access panels are very good candidates; i performed some strength tests yesterday on my elise and these provided near perfect reception. if you live in an area with fringe reception (i.e. higher latitudes for xm,their sats sit over the equator and/or no terrestrial repeater in your area) then you may want to mount the antenna under one of the inlets by the radiator under the hood. this will provide an unobstructed path but the heat may be an issue... i havent tried or tested this yet. Another thing to consider is that sirius uses a high elliptical orbit for its sats as opposed to xm's geostationary equatorial orbits; in this configuration, the sats pass overhead at high inclinations and at any time at least 2 of the 3 orbiting sats are above the horizon at opposite ends. this creates a very strong signal that will easily pass through the body regardless of vehicle position. with xm, you may have problems if your vehicle is positioned with the cockpit between the antenna and the horizon and you are out of range of the terrestrial repeaters.

One more idea to consider is to mount the antennas (xm and GPS) inverted on the underside of the vehicle and use the fact that the signal will reflect off of the roadway to hit the antenna. the antenna must be located near the edge of the vehicle, though. usually, its best to mount it in the rear of the vehicle about 406 inches from the body edge. again, with the mid engine design in the elise, heat may be a problem.

Finally, a very important issue that i havent seen discussed is that both the GPS and the xm/sirius antennas will only work properly if they have a suitable ground plane. This is crucial; while the antenna will work without it, you will lose 50% efficiency. The antennas are designed magentic to be used on a metal car body and therfore, the body acts as the ground plane. with the elise or any other fiberglass body car, it is important to place a small piece of metal underneath the antenna. the size of the metal should be a bare minimum of twice the area of the footprint of the antenna and 3-4x is better. the mercedes antenna kit that i designed uses a small square piece of 1/16" flat stock 3x the size of the antenna with a small tab on one side that acts as a mounting bracket. the addition of this piece makes all the difference when the signal is weak or partially obstructed.
 

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Hollywood said:
it doesnt NEED to have the speed sensor. it would be a little more acurate if there were one. and yes i did hook up the reverse light wire up.
the speed sensor is important for dead reckoning. when the gps antenna loses the signal, which does happen and often. the gyros and the speed pulse are used to keep track of the vehicle position. this makes a big difference in useability particularly if you live in a city with lots of tall buildings. if the pulse is not connected, you start to see the position indicator move slowly off of the road as the antenna loses gps lock and then it snaps back into position as the signal is reacquired.

getting a speed pulse on the elise shouldnt be a big problem... i know that on the UK elise, there was a orange/grey speed pulse wire at A5 on the cluster but it had a problem in that the peak to peak voltage was way too low for most nav systems to read properly.

since the federal elise uses CAN, it will definately be available over the bus which means that its simply a matter of putting together a microcontroller circuit to read the bus and output a pulse. the european CAN spec is pretty similar so i would bet that the lotus uses the same.

The CAN frame for speed pulse usually looks like this:

Code:
message ID	#bytes	period	data		
-----------------------------------------------------
002h		7	100 ms	01 02 03 04 05 06 07

byte 1,2: adjusted vehicle speed
byte 3,4: engine rpm
byte 5  : engine coolant temperature
byte 6  : speed pulse from left wheel ABS sensor (cycles 00-FF then rolls over)
byte 7  : speed pulse from right wheel ABS sensor (cycles 00-FF then rolls over)
I have some time today so i will tap in and log the CAN network so we can see exactly what information is being sent and what other neat things can be done with it.

building a controller to output a speed pulse is pretty easy; microchip makes a programmable microcontroller with the CAN interface onboard called the PIC18F452 that costs around $6.00 US. you also need a CAN transciever to interface to the bus voltage levels which costs $2-3 depending on whether the elise uses high spees or fault tolerant CAN. other than that, you need a crystal, 5v volt regulator, and a few capacitors and resistors (another $2-3). total cost is under $15 for something that i see selling for $250+.

Plus once you have a connection into the bus, theres lots of other cool things you can do... from programmable shift lights, e-shift, to having your radar detector warning come up on the instrument cluster digital display :cool:

BTW: if anyone has the wiring schematics for the ECU, cluster,and vehicle network, i would appreciate if someone could either post them or send them to me. i havent gotten my shop manual yet and those would really help in the meantime. thanks.
 

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rob13572468 said:
the speed sensor is important for dead reckoning. when the gps antenna loses the signal, which does happen and often. the gyros and the speed pulse are used to keep track of the vehicle position. this makes a big difference in useability particularly if you live in a city with lots of tall buildings. if the pulse is not connected, you start to see the position indicator move slowly off of the road as the antenna loses gps lock and then it snaps back into position as the signal is reacquired.
I have a radio with built in NAV that I'd love to use, but it's still sitting in the box because I didn't want to bother connecting it with no VSS. My Garmin IQ that I have suction cupped to the windshield has indicator that becomes very inaccurate when reception is spotty. If you can figure out a way to get a VSS signal on a federal Elise, I'd love to hear about it.
 

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i have the avic-n1 in my seqouia, its a pretty good unit got a lot of bells n whistles for the tecchie types, if you didnt already get it the new update came out about 3 weeks ago. they'll send it if you register it,. though i didn't check to see if it finally fixed the problem with the clock. its got rear view cam, and speech recognition available (though it doesn't work all that well )

i've aways wondered how well the g force function would work in my lotus, but i figured it'd never fit properly.

for a tad under a $1000 the avic-n1 has to be the best choice around, though there are some minor annoyances with it.
 

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charliex said:
i have the avic-n1 in my seqouia, its a pretty good unit got a lot of bells n whistles for the tecchie types, if you didnt already get it the new update came out about 3 weeks ago. they'll send it if you register it,. though i didn't check to see if it finally fixed the problem with the clock. its got rear view cam, and speech recognition available (though it doesn't work all that well )

i've aways wondered how well the g force function would work in my lotus, but i figured it'd never fit properly.

for a tad under a $1000 the avic-n1 has to be the best choice around, though there are some minor annoyances with it.
i agree that the avic-n1 is the best unit out. i have personally installed around over 15 and everyone loves them. the kenwood used to be the best before as it had touchscreen and the pioneer did not but with the new models having touchscreen, the pioneer has more functions and a better interface than the kenwood at a much lower price.


one more thing to note on the speedo pulse, there is a kit available that uses a magnetic sensor mounted at one of the wheels to generate a speed pulse... its not as elegant since the puls already exists otherwise but it will work.

http://thebassbin.co.uk/shop/product/products_id/243.html
 

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Joetz said:
Interesting...

I wonder how you magnetize the wheel to make it work?
You probably glue a small magnet to the wheel? Like a bike spedo.

How useable is the ABS sender that's already on the wheel?
 

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Ground Loop said:
You probably glue a small magnet to the wheel? Like a bike spedo.

How useable is the ABS sender that's already on the wheel?
i believe it uses a hall effect type sensor. it generates a magnetic field and then reads the rate of collapse which is effected by the steel in the radial belts. very similar to how the road sensors for traffic lights work. it does not need a magnet on the wheel...
 
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