[Geo_Ipe]

Hey!

Why are people getting Tacho's only on Marutis? I've been wanting to do this on my Santro Xing for such a long time! Just that the itch hasn't been that strong, also, no one here on TBHP seems to have done it on a Hyundai!

If anyone has done it, please do share the details!

[Sankar]

Originally Posted by a4anurag

Putting up another successful D.I.Y that I completed. Two friends came up to me asking if there was a possibility to add a tachometer in their cars. The two car's in question are:

1. 2003, WagonR LXi and
   
   
2. 2009, A-Star LXi

As seen both cars being the low end variants, they do not get tachometers from factory. It was not that difficult to get to wiring ready but difficulty was in getting the parts from MGP. Also it is no short of yoga that one needs to do for completing all the wiring properly.

Sincere Thanks to BHPian LeoShashi for helping me source the Tachometers and panels from Delhi/Ranchi and to ship it to me and Mr Vinesh to ship me the tachometer bracket for A-Star.

Also thanks to BHPian LeoShashi, BHPian interc00led and BHPian im_srini for patiently answering all my silly doubts that I had all throughout since I took up this DIY project over 8 months ago. Also thanks to DBHPian Sankar for confirming the possibility to fix A-Star tachometer in the LXi variant.

Now, coming to the DIY, I'll explain a bit in detail taking each car in isolation so focus is better than making it generic.

Congratulations and the connections look proper When installting electrical accessories attention to detail in wiring is always underplayed. Its good to be be fussy about making proper electrical connections while adding accessories.

In 2011 someone I know in Kannur,KL had the tacho installed in his AStar by the dealer workshop, and they tapped the brown wire to EPS module for the signal. Same time I also bought the OE tacho for my Astar VXI but I sold the car soon after.

[chiranjitp]

Originally Posted by a4anurag

2) Maruti A-Star LXi – 2009 model

With the experience of installation that we gathered on the WagonR, going about the same on the A-Star wasn’t difficult expect that we stopped at the point where we were searching for the brown wire behind the instrument console but later got a doubt that the EPS unit should definitely be getting this wire for the EPS to work accordingly. It was the right thing as the coupler had the wire in it. From here on things were easy except for parts sourcing.

First of all thanks for sharing a brilliant DIY. I too got inspired by your thread & wanted to have an OEM tachometer in my 2001 Maruti Zen Vxi deluxe. As zen never did came with a tachometer from the factory, I only looked for the brown wire in EPS module like the Astar & I did find one brown wire.

Next part was to source the Ritz tachometer, the MGP store manager said that he could arrange for one petrol Ritz tachometer from the warehouse. But as luck would have it, when I went to pick up the tachometer I was informed that the tachometer is broken but a tachometer for the diesel Ritz is available. Patience is not one of my strongest qualities so I picked up the Ritz diesel tachometer hoping that it would work & the only difference would be a lower redline.

I got the installation done in early 2017 from a accessories store, the brown wire from the EPS module was the correct wire for RPM signal. But the RPMs displaced by the tachometer were absurd, it used to show idling RPM around 2000 RPM & a slight tap on the accelerator pedal would mean the tachometer needle would be near the redline.

So, now that I am a member here & I can interact with you guys, I would like to try to do a proper installation. Should I order a petrol Ritz tachometer? Will it work properly or the RPM signal that my old EPS module sends can't be read by the new Ritz tachometer? My knowledge of electrical/ electronics is negligible.

The EPS module



The famous brown wire



The Ritz diesel tachometer

[audioholic]

Originally Posted by chiranjitp

First of all thanks for sharing a brilliant DIY. I too got inspired by your thread & wanted to have an OEM tachometer in my 2001 Maruti Zen Vxi deluxe. As zen never did came with a tachometer from the factory, I only looked for the brown wire in EPS module like the Astar & I did find one brown wire.

So, now that I am a member here & I can interact with you guys, I would like to try to do a proper installation. Should I order a petrol Ritz tachometer? Will it work properly or the RPM signal that my old EPS module sends can't be read by the new Ritz tachometer? My knowledge of electrical/ electronics is

Since you are speaking about a 2001 Zen, it is better you consult the service manual of either the Zen or any other similar Suzuki car of the same vintage top get to know the actual wiring scheme. It will not always be the brown wire and the same connector. My hunch is that they have wired the Tacho to some other 12V signal. There is a slight variation in the voltage when you press the accelerator. It is typically within 0.5V for a moment before the voltage is adjusted at the alternator. Hence you will see a spike when you revv the engine.

Even if the pin is right, the RPM signal might be transmitted in a different way compared to the later year vehicles. Hence try to dig into some document or probe the pins with a multimeter to check which is the right pin to attack. The last time I had heard of this issue was from @paragsachania when he installed it on a SwiftD. I guess he will be able to give an idea since he got it right later.

[chiranjitp]

Originally Posted by audioholic

My hunch is that they have wired the Tacho to some other 12V signal. There is a slight variation in the voltage when you press the accelerator. It is typically within 0.5V for a moment before the voltage is adjusted at the alternator. Hence you will see a spike when you revv the engine.

The installer did connect the tachometer wire to all the wires in the PS module & among them only the brown wire made the tachometer move w.r.t accelerator pedal. I do have one service manual in pdf form of the ZEN, it does not specify anything about the color of the wire that carries the RPM signal.

Originally Posted by audioholic

Even if the pin is right, the RPM signal might be transmitted in a different way compared to the later year vehicles.

To me this seems the most likely cause, my car which is from 2001 might transmit the RPM signal in a different way than a newer model. Is there a chance that the diesel tachometer will require the RPM signal to be transmitted in a different way?

[audioholic]

Originally Posted by chiranjitp

To me this seems the most likely cause, my car which is from 2001 might transmit the RPM signal in a different way than a newer model. Is there a chance that the diesel tachometer will require the RPM signal to be transmitted in a different way?

Nope. There is no difference between petrol and diesel tachometer. The signal IIRC is a 5V or 12V PWM signal in both cases. Either tacho will work in the same fashion, just that the range will differ. But this was the convention for cars between 2005-2015 roughly. After that the electrical architecture has changed and you will no longer find this same brown wire in cars like the Ciaz, Celerio, Baleno etc. Thats because all the data between control modules are sent via CAN. Hence you cannot install such a tachometer to the latest cars from the Maruti stable.

Hence, before experimenting, please verify if what you are doing is technically correct. Else it will lead to trouble especially if you end up connecting in such a way that the PS module will burn out or the tacho.

[peterjim13]

Originally Posted by a4anurag

2) A-Star LXi

Hope the thread will be helpful for many. I have put down most of the finer details that I could and keep the matter in simple format so it is understood by all.

Thanks for reading guys.

Sorry for pulling this thread up. Quite interesting to see this as my wife have been using a pre-owned A-star Zxi Automatic. Whenever I drive the car (I use it as a beater car, not when my wife is around) I have always felt that a tachometer would be a great add on.

Can we still source OEM tacho's from the market?

[Tom Sooraj]

Originally Posted by peterjim13

Can we still source OEM tacho's from the market?

Yes, you can buy the A-Star tachometer from boodmo.com.