Gear selection indicator

[Holdens Rule]

I need some help on this one. My car is a series 1 calais (99) but I have put a VX Calais BCM into it and a cluster from a 2002 statesman both have been programed by Holden. My understanding from what I've been told is that the BCM would enable the gear selection on the cluster to work but it doesn't. Has anyone done this mod and if so what did you have to do? I'm guessing gear selection switch but am hoping that I don't have to rewire the cluster, any help would be great.

[wrx884]

Do all stato clusters normally light up the gear selectors? ive not had my hands on 1 yet but best way 2 tell is check if the LEDs r inside there.

[Holdens Rule]

This one has the writing on the face and bulbs in the back plus 2002 stato should have it anyway.

[Galixia]

my wh stato has all the gears displayed in the dash between the tacho and speedo as well as having all the gears lit up down beside the selector. i havent had a look to see how it works but im assuming there must be a wire running up to the dash or something

[viper2104]

Have the same problem myself - the issue isn't what BCM or dash, it's actually the engine wiring harness itself - the gearbox has an extra plug on it that in the earlier VT series wasn't used.
All ECU's have vacant inputs for this plugs wiring, it just wasn't used in the earlier models. Technically you should be able to run the wires from the gearbox to the ecu, which will in turn tell the BCM the new information in order to activate the dash gear lights.
I gave up on it, it's simply not worth it for the work required, but to each their own.

[Holdens Rule]

So if I changed my engine harness with one from say a VX Calais then it should work? The gearbox will still be alright or dies it need a later gearbox also and how hard would it be to change the harness?

[mwb235]

Yep if you fit a VTII/VX Berlina/Calais or WH engine harness (plus a PRND321 cluster) it will work, but there is an easier, quicker and cheaper way.

I did this in my 1998 VT series 1 Calais V6 s/c late last year. It's actually not that hard to get the PRND321 lights to work on any VT1 V6 or V6 s/c auto as they all have the PRND321 socket, covered up with a blanking plate which is easily unattached. (But you definitely can't do this to a VT1 5L V8 as the auto transmission doesn't have the necessary gear selector plug (this is why VT series 1's don't have the PRND321 lights - it was so the V6 and V8 models had equal "features").

You need the following:
(1) a VT II / VX Berlina/Calais or WH dash cluster with the PRND321 lights
(2) some reasonable gauge auto wire (autobarn/supercheap/repco etc)
(3) the Holden VT II wiring diagram (supplement 14E i think it was); and
(4) four "pins" of a similar size and shape off a wiring harness (needed to connect the PRND321 wiring to the PCM) - you insert these 4 pins into the 4 "cavities" (empty ports in the plug) as set out below.

Other than fit the VTII/VX or WH dash cluster first (obvious, i know) the only other thing you need is - connect 4 wires between the PCM (body computer behind passenger side kick panel) and the auto transmission, passenger side (only accessible with the car on ramps or a hoist). I've attached a photograph of part of the 14E supplement i photocopied which i needed to see what colour & pin number the 4 wires are. The pin configuration is as follows:

PCM: cavity E6 = Auto Transmission PRND321 socket: cavity A
(Blue wire / White trace)
PCM: cavity E7 = Auto Transmission PRND321 socket: cavity D
(Yellow wire)
PCM: cavity E8 = Auto Transmission PRND321 socket: cavity B
(Grey wire)
PCM: cavity F15 = Auto Transmission PRND321 socket: cavity C
(White wire)

I had a couple of damaged VT body harnesses lying around, so i already had the PCM "pins" (if you don't have these - check for damaged harnesses at a wreckers, or cut them off yourself at somewhere like Pick'n'Payless in Blacktown [Sydney] NSW).

I reckon the hardest part was figuring out how to securely attach the four wires to the four pins on the PRND321 socket (on the auto transmission). This is because the plug needed appears to be a unique shape - i could not find one like it on an old complete VT series 1 harness i also had. (N.B. the PRND321 plugs were present only on VTII/VX Berlina/Calais and the WH models). So i got four pins that were the same size/shape from another plug (cut them out carefully with a stanley knife) and simply eased them on to the pins in the PRND321 socket. I then stuck some silicone in the socket hole to secure/seal up the pins so they wouldn't get loose and/or short, etc.

I then fed the wires up to the firewall (passenger side, near to aircon pipes), poked them through an existing grommet in the firewall to behind the glovebox. Then i spliced in the four "pins" i got off another plug and slotted them in to the relevant "cavities" on the PCM plugs. Easy!

Of course i should point out the obvious (again!) - please do all this with the negative battery terminal disconnected!

After 12 months and 20000km the PRND321 lights still work 100%, so there's no need to waste money on a VTII/VX Berlina/Calais or WH harness (which i had considered but they are hard to get separate from an engine, and very pricey even if you can!).

Good luck. It really isn't that hard or costly if you are patient.

[Holdens Rule]

I reckon I can get a engine wiring harness pretty cheap so I might go in that direction and use those plugs, cheers for the help guys.

[Holdens Rule]

I can get my hands on a engine harness pretty cheap but how hard is it to remove? Does anyone know how many plugs there are to disconnect and if it will come straight out or do you need to remove things like alternater etc?

[mwb235]

It's probably isn't hard for someone who has replaced one before, but i wasn't keen to try so i can't help you.

[gibbo]

mwb235, I know this is an old thread, would you still have the repair manual with the switch operation chart that is in the picture above? Is there any more to that chart. It looks like there is fold in the middle of it. I am trying to adapt the prnd4321 switch to my hilux .
Cheers

[mwb235]

Hi gibbo, i only photocopied one large long page out of a VT Series II "14E" supplement / workshop manual. The pages were about the size of three A4 pages joined together. I used to know someone at a dealership (who has since left) who gave me access and let me photocopy the one large page i wanted which was all i needed to get this mod to work. There was only one page covering the PRND321 lights specifically so i didn't photocopy anything else.

I've stuck together the three A4 sheets as one large page and took some pics of it on my digital camera. I don't know if these will be readable once posted on this forum. If they're not send me a PM and we can discuss alternative arrangements.

If you know someone at a Holden Dealership well (who can get you access to their manuals etc) you could ask them. Or if you have some spare $$ and want to buy one yourself, they were still available in late-2007 thru Holden Spare Parts. The workshop manual details as follows:

Commodore VT 1997-2000 Workshop Manual, Volume 14E -Series II Wiring Diagrams
part number 92142412 cost $190.00

In case it helps, i've also attached a pic of the 4-pin PRND321 transmission plug which i managed to "find" at a wreckers one day. I still haven't bothered (and probably won't bother) to use it to replace my custom wiring job (that i discussed in Post #7) as it's still working 100%.

[gibbo]

Thats exactly what I was after, I can see them fine.
cheers for that.