• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Sensor output values, and how the dash / computer interprets them

Renegade_Azzy

NAXJA Forum User
Location
Finleyville, PA
Is there a place that I can find sensor output values (like the temp sensor runs 200-300 ohms) and what sort of signal needs to go to the tach and speedo?

I am building up a test and calibration setup for my new gauge kits (thread on that here), and would like to be able to tell the things to sit dead center and be able to move a pot or 1 and run through the range of motion so I can not only test the cluster, but make sure the needles are in the right places.
 
Late model (97 and later) you're going to need the ECU involved, since basically the entire cluster is driven by the CCD bus from the ECU's data. 96 through 91 everything should be pretty easy except the tach (iirc, they use a pulse train signal, 33.3Hz for every 1000rpm, but I may be misremembering this) and speedo (8000 pulse per mile signal to the ECU, I forget the pulse rate from the ECU to the cluster) and 87-90 I know very little.

That being said - you can read most of the same data out using a ScanGauge II or equivalent from the OBD port, and at one point I found a writeup on decoding CCD bus data that was pretty helpful to me, pretty sure you could use it to figure out how to encode the data as well, at which point you could just send whatever calibration/known values to the cluster you want to. I'll see if I can find it again.

Oh, another thing - IIRC there is a self-calibration routine built into the cluster, I forget how to enter it but once you get it started it just cycles through various tests that will let you see if everything's lined up right.
 
Pre-97 is easy, my designs can work round the needle setup, so no n eed to remove them. 97-01 is where it gets tricky. My wife is not too keen on me tearing apart her dash to test things out again and again, especially now that we just have 2 enclosed vehicles, mine being a 96.

So the self calibration setup is not entirely helpful for these purposes, unless you can power the cluster and get the same result. Anyone know the pin-out for power on these? Ive got a spare one to test the theory....
 
I THINK you can... not entirely sure. Lemme find my FSM.
 
I believe the wires you need are pink, and white/black. Pink is constant, white/black is key-on. I think.

Orange for the lights, black/green for ground. Not 100% certain though. I'm trying to find something more helpful than that.
 
Last edited:
Pinout (from 99 XJ manual):
C1 pin 1 tan/black = liftgate open warning lamp (not sure if this is +12V=on or ground=on, check section 8W-44-8 of your FSM if you need this info)
C1 pin 2 gray/white = brake warning indicator switch sense (ground to illuminate)
C1 pin 3 orange = backlighting/cluster illumination (0V = off, +12V = full brightness)
C1 pin 4 light green/orange = ABS indicator switch (ground to illuminate ABS warning lamp)
C1 pin 5 red/orange = high beam indicator (+12V to illuminate)
C1 pin 6 black/light green = ground
C1 pin 7 black/light blue = washer fluid level switch sense (to ground)
C1 pin 8 white/black = fused ignition switch, hot in start/run
C1 pin 9 pink = fused B+, always hot
C1 pin 10 light green/white = left turn signal indicator (+12V to illuminate)

C2 pin 1 white/black = CCD-
C2 pin 2 violet/brown = CCD+
C2 pin 3 light blue/white = rear window defogger relay control, cluster grounds this to enable rear defogger grid
C2 pin 4 dark blue/white = rear window defogger request switch, ground to activate rear window defogger grid
C2 pin 5 black/red = transfer case parttime switch sense (ground to illuminate)
C2 pin 6 tan = right turn signal indicator (+12V to illuminate)
C2 pin 7 black/white = transfer case fulltime switch sense (ground to illuminate)
C2 pin 8 light blue = chime control (ground to sound warning chime for headlamps/doors left ajar or key in ignition)
C2 pin 9 black/light green = ground
C2 pin 10 light green/red = seat belt switch sense (to ground)

Warning... there are two white/black wires. One is ignition switched +12V, the other is CCD- bus signal. You can tell them apart because the CCD- one will be part of a twisted pair of wires with the CCD+ signal being the other one, which is violet/brown. The one that is ignition switched +12V will not be twisted around anything.
 
Well, Ive found something interesting. I have 2 clusters here from this gen, one is from a 99 XJ, and is the "idiot light" version with the big fuel gauge, and the other is rom a 98 TJ, with full gauges.

The sequence on the XJ cluster is close, but a tad off. I can get it to run a test sequence with the warning lights, but no needle movement. Beeps too!

The other I can get to run though 5 warning lights, and can trigger the others with certain pins, and then hit the backlight on, but not all at once, and no luck on needles either. Thats all just with some exploring with jumpers and a 12v source.
 
Back
Top