Tachometer...

[Lazy-Ferret]

So... how does a diesel Tachometer work?

I know a petrol one measures the pulses on the coil, but what does it measure on a diesel?

The one on the T1 is not working, it goes up, but never comes down until you either go over a bump, turn the ignition off... see even that is silly, as there is no ignition on a diesel.:doh

 

[solarman216]

W connector on the alternator is one method, think it is W anyway it is a extra wire, Rick

 

[96terrano]

Yup, alternator on the terrano, I found this out when I forgot to connect the belt, no rpms :doh

 

[rayf3262]

If it's a TDi then the tacho signal is derived from the CKP/ECU.
The tacho output from the ECU is on pin 439 and this goes directly to pin 23 on the instrument cluster.

 

[solarman216]

If it's a TDi then the tacho signal is derived from the CKP/ECU.
The tacho output from the ECU is on pin 439 and this goes directly to pin 23 on the instrument cluster.

I nearly got caught by this one, it is a T1 so guess too early for ECU stuff, Rick

 

[rayf3262]

I nearly got caught by this one, it is a T1 so guess too early for ECU stuff, Rick

Lazy-Ferret

Location: Sevenoaks, Kent
Vehicle: Terrano 2.7TDi SE Touring
Posts: 864

?????

 

[Lazy-Ferret]

Thanks, it is a non inter cooler, so I will have a look around the alternator, I don't think it even has an ECU, I only found the key to wind it's spring up under the rear seats the other day.

While looking into this, I just discovered it does not have fuses on the feeds from the battery, it has several fusable wires...

These are lengths of wire about 5 inches long, running between 2 connectors. These are designed to burn out, should you draw too much current, but thoughtfully, they are placed right beside the battery and plastic power steering reservoir. Hope I never blow one...

 

[Lazy-Ferret]

Lazy-Ferret

Location: Sevenoaks, Kent
Vehicle: Terrano 2.7TDi SE Touring
Posts: 864

?????

:lol
It only lets you put one car in there, and my T2 came first, so stays in there...

I have listed them both in my signature, and I did say T1 in the OP.

 

[rayf3262]

Thanks, it is a non inter cooler, so I will have a look around the alternator, I don't think it even has an ECU, I only found the key to wind it's spring up under the rear seats the other day.

While looking into this, I just discovered it does not have fuses on the feeds from the battery, it has several fusable wires...

These are lengths of wire about 5 inches long, running between 2 connectors. These are designed to burn out, should you draw too much current, but thoughtfully, they are placed right beside the battery and plastic power steering reservoir. Hope I never blow one...

IIRC one of those cleverly placed/designed "fuses" is for the glow plugs.....

 

[rayf3262]

The black plastic fascia on the instrument cluster has a tendancy to warp slightly, this can cause the pointer to stick slightly. Look carefully for any slight marking on the backing behind the area the arse end of the pointer travels in...

 

[Lazy-Ferret]

The black plastic fascia on the instrument cluster has a tendancy to warp slightly, this can cause the pointer to stick slightly. Look carefully for any slight marking on the backing behind the area the arse end of the pointer travels in...

Cheers :thumbs, my first thought was it looked like it was sticking, but the fact it immediately returns to zero when you turn the car off, kind of threw a spanner at that thought.

Good clue about looking for scuffs though, will do that. Reading on line tonight, and apparently the fascia on the T1 is a real git to remove as well, so was kind of hoping for an easy wire fix...:lol