Hi All Another little job to do whilst I am replacing the leaking heater hoses on my 1986 Euro Testarossa, is to get the mid console mounted Odometer repaired/working. The main dashboard speedometer appears to work fine so I’m assuming the gearbox/engine speed sensor is ok and it’s a failure of the odometer unit (both the permanent odo and trip meters don’t work). (FYI - The separate clock above the odometer works fine, in the picture it’s off because power is turned off in the car…) Is there an existing forum thread which covers diagnostics and what signals / wires to check, then leading to potential fix? Be handy to know before I start stripping out panels to start on the heater hoses replacement and removing the odometer too…. Here in the UK there are very few specialists who will touch or work on the Veglia Borletti unit… not a cheap or simple job just to send abroad… is it a common issue such as failed or damaged plastic gears etc.? Thanks in advance. Image Unavailable, Please Login
I think you'd be safe to say it's an internal problem. Looking at the Euro TR wiring diagrams, the unit seems to supply power to the speed sensor (on a green wire). The sensor then returns a speed signal to odometer on a red/black wire. There is a pigtail on the back of the odometer plug which splits the signal into two ... one path going inside the odometer and the other one going to the speedo. Since your speedo is working, that tells us that the odometer is sending power to the speed sensor and the speed sensor is sending a good signal to the odometer plug (and the speedo). All that leaves is a yellow wire for background lighting and a black earth wire.... and the internal electromechanics. External wiring diagram here: https://www.dropbox.com/t/ZHQQCSVTrPwCLm2m
Thank you for the reply and very useful information, that will help with at least ruling out any wiring issues and it’s a sanity check too the issues appear to be with the unit itself and nothing else currently. I will update the post with more information as it comes Best Regards
I see your day counter is between 1111 and 2222. Can you turn those to 0000 again and see if your odometer is working again....
I managed to remove the Odometer and clock unit from the central console. There are 4x screws holding it in place from the back. You have to remove the 2x centralconsole side footwell panels first and then you can get a Philips headed screwdriver to unscrew the unit. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
After being unsuccessful in finding a specialist instrument repairer in the UK (all the ones I have contacted won't touch a Veglia Borletti due to spares unavailable etc...). I have decided to disassemble the Odometer and attempt a repair myself. Here are some photos and information to help others in future... It's not too scary to disassemble, similar to a mechanical clock with added electronics. To remove the outer casing and front fascia, to reveal the electronics + mechanics is as follows: There's a certain sequence of screws to remove carefully, to remove the clock plus casing. Note: only 1x of the knobs actually comes off the front as the 2nd is fixed to the pcb mounted potentiometer and there is a small white plastic collar to unscrew, once you carefully pull off the knob... you will then be able to separate the front fascia away and remove the internal electronics and mechanical parts. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login View attachment 6780734 View attachment 6977181 View attachment 7055151
Next was to remove the screws and posts holding the main mechanical assembly to the front fascia, becareful to not lose any gears or screws! (Unplugging the motor unit from the pcb and lamp from the fascia will ease the process) Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Now to inspect some of the mechanical gears, motor and related components for any damage or excessive wear. Thankfully none of my gears or mechanical parts are damaged or worn (these are the items NLA and would have to be reproduced). The worm gears which rotate the odometer + trip meter counters freely turn, plus the gears eventually connected up to the electric motor. The old grease will need cleaning off and replenishing, which I will do next. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
As the physical mechanics appear to be in very good condition (just needs a clean and regrease), the problem I suspect will be the electronics (far easier to repair than worn or damaged gears which are NLA). 1. I noticed the main PCB 4x pin connector where the clock plugs into has loose dry solder joints which will need resoldering, plus the PCB conductive tracks are starting to bubble on the underneath but are at least not broken. 2. I will also test the gearing motor to hopefully eliminate this as the issue, will have to ring it up to a power supply. Should the motor be fine, my money is on one of the onboard ICs or transistors. 3) I will probably replace to refurbish the transistors and ICs anyway….. Shopping list for the onboard transistors and ICs are as follows (need to research the latest succession parts where applicable)= 1x BC 337 -1N Transistor 1x BC 237 B Transistor 1x 513 TIP 127 (Motorola) IC/Transistor 1x BDB 02C 609K (Motorola) Transistor 1x 92967 RCA 606 IC 1x MC1455 P1 T8545 (Motorola) IC 1x Mini wedge bulb 12v 1.2w
(EDIT: Sorry cross-posted) Is it obvious which wires are for the electric motor? Can you apply a small voltage from, say, a small 9 volt battery to see if the motor runs (or even a AA battery). Are there any numbers on the motor itself? What's the number on the power transistor mounted on the heat sink? Seems silly to say this when it is such old technology. You can probably find every component online, other than the mechanical bits.
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Hi Ian The motor is powered via a white 2 pin PCB connector with red and blue wires. Good point I will try powering the motor with a low voltage power supply whilst unplugged from the trip counters… unfortunately no markings on the motor at all unless it’s stamped on the mounting collar plate, but haven’t completely stripped it away from the gearbox. The power transistor attached to the heat sink has the part number of: 513 TIP127 (Motorola symbol).. I will get a multimeter and start some additional diagnostics tomorrow…. Definitely agree on the replacement alternative electronic components being a lot easier to source than the NLA mechanics, I feel a lot more confident that it can be fixed now. Will post more findings and progress soon. Thanks
Seems like the datasheets for these components are readily available. It should help with finding suitable replacements. e.g. Motorola TIP127 https://datasheetspdf.com/pdf-file/1074660/InchangeSemiconductor/TIP127/1 PNP Darlington Power Transistor e.g. Motorola BDB02C https://pdf1.alldatasheet.com/datasheet-pdf/view/2939/MOTOROLA/BDB02C.html So a 1 watt PNP transistor.
A few more datasheets: https://www.onsemi.com/pdf/datasheet/bc337-d.pdf NPN multipurpose transistor (in driver or amplifier circuits). Readily available. https://www.farnell.com/datasheets/2861481.pdf Another multipurpose NPN transistor No datasheet for this one. I see this number has been mentioned on Alfa forums in regards to speedometer circuits. https://www.alfabb.com/threads/troubleshooting-1985-86-speedo.682270/ This link mentions FChat: https://www.ferrarichat.com/forum/posts/142735822/ https://pdf1.alldatasheet.com/datasheet-pdf/view/11991/ONSEMI/MC1455P1.html https://pdf1.alldatasheet.com/datasheet-pdf/view/516656/TI/MC1455P1.html etc... A typical replacement for an NE555 timer with adjustable duty cycle.
Thanks again for sending through the data sheets which are very useful, I will now order new ICs and Transistors. As a further update the motor is in good working order, I put some dress making pins into the white plug end with the red and blue motor power wires, and then attached wire leads to a 3v DC power source - at that point the motor and lower gears worked fine . Next I cleaned up the old hardened up grease by the main motor wom gear and 2x upright pinion gears which then feed up to the distance rotary counters.... putting some fresh grease afterwards. Now that the mechanicals and motor are all confirmed to be working. The problem will be with the electronics, which I will replace the components.... Further updates to come when I source some components. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
What kind of grease are you using? Just remembered this message thread: https://www.ferrarichat.com/forum/posts/148194028/
I managed to order most of the required ICs and Transistors apart from the 92967 RCA 606, also double checked and it’s a BC337-16 fitted and not BC337-1N. 1x BC 337 -16 Transistor 1x BC 237 B Transistor 1x 513 TIP 127 (Motorola) IC/Transistor 1x BDB 02C 609K (Motorola) Transistor 1x 92967 RCA 606 IC 1x MC1455 P1 T8545 (Motorola) IC 1x Mini wedge bulb 12v 1.2w Struggling to determine from the previous threads and internet searches what is a suitable replacement for the 92967 IC…. Not sure if any further information is available or clarity?
Ah very good point I just used a blob of petroleum grease…. But better get some proper plastic friendly stuff….
Next mission is to track down one of these or suitable replacement…. Image Unavailable, Please Login Image Unavailable, Please Login
If you're going to replace every component on the board, you may want to check the diodes and capacitors. Here's a post on the Technical Forum relating to a 308GT4 https://www.ferrarichat.com/forum/posts/146485982/ There seems to be a lot of smart folks around who may be able to help you. @alhbln seems to be still around on the forums