Rev Counter?

[Seamus]

Chaps/Chapesses,

Think we've got a dead Rev counter and looking for a replacement. We think the one we have has come from a diesel (goes upto 6,000 rpm). Im guessing a petrol counter will therefore go upto 7,000 or 8,000 maybe, as you see on most other vehicles? I've put a post in the wanted section but if anyone has one they want to sell let me know!

cheers Sean.

[SyncroSwede]

The ones I have seen on eBay go for over £100 so I've not bothered (even though my analogue clock has conked out!). The waterboxers only rev to 5400rpm but I believe the rev counters are a little different. There is a thread somewhere where people have fitted an after market rev counter in a pod to one side. Probably the way I will go in time.

[Aidan]

Sean
do all the oil lights do the correct thing at start up ? or is your bod circuit bypassed, basically the coil signal is used for both the rev counter and bod circuit and the edge connector of the board is prone to wear and the split signal track goes through two 180 degree turns underneath the clip.
If it's just a broken track then it's possible to effect a good repair using electrically conductive paint from maplins/RS etc.. I've done a few such repairs successfully.
As Mal says they go for big money in working condition
The petrol one won't have a glow plug led and the green band is 2k-4k rpm with shaded green just above and below, red band just over 5k rpm, diesel bands are 2k-3.8k and the shaded green above 3.8 almost reaches the red shaded area below 5k

[Seamus]

Thanks Aidan,

its deffo a petrol counter then...



as for the startup lights, well im not 100% convinced, the oil light very briefly flashes on and off and I dont have a battery light, the connector looks in very good nick with no wear so i think that maybe there are some connectors in the wrong places maybe...?

The other idea I had was to get maybe a Mk1 Gold variant, they look very similar but not sure what the connector is on the back and how I'd get round that, they go for next to nothing on evilbay!

[AngeloEvs]

Take the dash out and check all the functions and repair/refurb before you start splashing hard earned cash on a replacement. Check that your loom edge connector is compatible with the dashboard just in case.

[Aidan]

Dynamic oil pressure warning system
start up sequence lights
ignition on
alternator warning light comes on and stays on
oil warning light flashes once a second
temp guage warning light flashes whilst system does self checks then goes out - I always wait till it has gone out before turning the key to start, as it may continue to flash for some time, even continually, otherwise, though this is usually due to a damp relay due to water ingress from windscreen and condensation cycle behind the dash ime.

on start
alternator warning light goes out
oil warning light goes out
temp guage light stays out

no lights should be on, so that if they do come on that's the warning to stop and check


if this isn't happening it suggests either you have wiring fault or that the bod circuit is faulty and the lack of rev counter could be due to bod circuit issue as the signal wire from the alternator is split on the flexible circuit to go to the two seperate units

the golf units are completely different rev range and wiring is slightly different, stick with the correct parts don't go introducing unknowns into the system unless you have a complete understanding of the wiring and circuits and know how to test and modify - I use Angelo for checking my boards as I don't have an oscilloscope or the electronic knowledge etc....

[Seamus]

thanks amillion chaps, loads of good advice there, with a little more digging the plot thickens...

looking at the connector it reads the following... (in my best german!)

1 = INSTR.BEL
2 = FERNLICHT
3 = ALLGEM
4 = FREI(KL.1)
5 = + UHR
6 = TEMP.
7 = TANK
8 = + ALLGEM.
9 = KL.1
10 = BLINKERKONTR.
11 = LADEKONTR.
12 = 1.8 BAR
13 = 0.3 BAR
14 = DIESEL/OXS/CAT

Number 14 is a slight concern as this seems to show a 'diesel' description.

I have also managed to find a couple of pics of a diagram another member sent me a while back, these are as follows...

early version...




late version...



I am certain I have the later version and I am pretty sure the problem is down to getting the right wires into the right connectors, I am 'kin determined to get this fixed as it's really the last little annoying job to get done on the whole van.

[AngeloEvs]

Ignore pin 14 for Diesel as all dashes have provision for a glow plug LED!

Thats the later dash, is the dash the original one fitted? If not.....1985 saw the changeover in the design of the membrane pcb to the later pin connections (as you have listed) but early production dashes (and vans made in '85) did not have the DOP's pcb installed (Buzzer of doom) and no connection from the ignition coil was provided even though the membranes and dashes appear identical. Your van is an '85 and I would check that you do have the coil feed signal actually arriving at the multiconnector pin 9. The oil pressure LED on these dashes was connected directly to the oil pressure switch as on earlier vans.

I have repaired and overhauled many of these dashes and seen a number of production variations around the period '85 to '87'

[Seamus]

Ignore pin 14 for Diesel as all dashes have provision for a glow plug LED!

Thats the later dash, is the dash the original one fitted? If not.....1985 saw the changeover in the design of the membrane pcb to the later pin connections (as you have listed) but early production dashes (and vans made in '85) did not have the DOP's pcb installed (Buzzer of doom) and no connection from the ignition coil was provided even though the membranes and dashes appear identical. Your van is an '85 and I would check that you do have the coil feed signal actually arriving at the multiconnector pin 9. The oil pressure LED on these dashes was connected directly to the oil pressure switch as on earlier vans.

no mate, its been a replacement, the original was in a real state - drilled holes cracked glass and naf digital clocks galore, I got this on ebay for only £30 complete and by the prices you see at the moment I think I got a bit of a steel, however only if I get the darn thing working I guess

here's the back of the pcb, Im not convinced there is BoD installed?

connector is in perfect nick...





I am no auto electrician and am starting to get a little concerned that I may do more harm than good playing with the electrics, it's a shame your up in Norfolk Angelo

I May have to go back to Doug when he's all fixed and arm him with all this info and let him do his magic me thinks!

[Aidan]

ok so the bit of tape on the back of the speedo is holding that bit of the flexi circuit in place, the bod circuit is inside the speedo and the six pin connector to the left of the tape is where it connects, so easy to check, if there's no pins sticking out of the speedo to connect to the foil you have no bod circuit

note that someone has taken of the sticker that covered the hole to adjust the rev counter so it may have been messed with

[AngeloEvs]

As I said, with an '85 Van you need to check the Loom Multiconnector does have the feed for the Rev Counter arriving at PIn 9 and that you have the correct wiring sequence for the later dashboard. BTW, without the BOD pcb installed the Rev Counter will function as normal but the oil pressure LED will not.

[Seamus]

Ok,

I've done some digging without getting too involved as I am not 100% comptetant. It looks like there is no feed to pin 9 on the connector, there also looks like there is no BoD. Is there a fool proof way of connecting this up or would it be easier to buy an aftermarket one, I would much prefer to connect this up if poss as I dont want a load of add on's sat on the dash.

Sorry to ask a little more but if anyone could pen me a quick step by step of what to connect to where I would be eternally grateful!

[Aidan]

Sean
I can supply you with petrol bod circuit, it simply clips into th einside of the speedo housing which you access by unscrewing the four screws if present around the back and remove the sticky tape

[Seamus]

Sean
I can supply you with petrol bod circuit, it simply clips into th einside of the speedo housing which you access by unscrewing the four screws if present around the back and remove the sticky tape

pm sent mate, thanks again!

[AngeloEvs]

You will still need to hitch a wire from the ignition coil and somehow get it to pin 9 of the multiconnector otherwise you will have no rev counter working and the bod will not function as it should either. Check to see if you have a wire going to pin 14 (you should have one even though its not needed on petrol models), if you have I will explain how to use this wire for your Rev counter by re inserting it into the pin 9 location. Take a peek, let me know and I will guide you through the process.