Electrical woes

[Jethro]

Trying to rescuscitate a dead Maverick TDI. Why, when I turn on the ignition does the rev counter go up and stick about 1200 revs?

Also nothing happens when I try the starter except for a click and eveything dies.

 

[zippy656]

daft question..

battery terminals, make sure clean and tight..
some time they get a crack in them, all works but not enought to start teh car.

also look at earth straps for engin and battery, both can cause this kind of staring issue...

 

[jims-terrano]

Try turning ignition very slowly as a faulty ignition switch (seperate from ignition lock) can cause the click you describe.

Jim T

 

[zippy656]

Try turning ignition very slowly as a faulty ignition switch (seperate from ignition lock) can cause the click you describe.

Jim T

good one, id forgoten that...



VERY VERY slowly...

 

[clivvy]

yep, but not sure about the revs going up if the car hasnt even started? is that what you mean? you turn the ignition TO start, the rev counter goes up without the car starting, or do you mean your turning the key to start, the rev counter rises but the engine doesnt crank?
odd.

This suggests a furthur electrical fault to me, but I would certainly check the main positive to starter, the two big earth wires (they corrode in places where the wire meets the body of the vehicle)

also the ignition seems to be working, if its just clicking, then the starter is bad. I only say this because I had a similar issue. replaced my ignition switch and still had the "click", replaced the starter and that fixed it. I had already done the wiring as above, and the final fix was the starter itself....

 

[ocelot]

sounds like there is some faulty wiring with the alternator, the W connection should be connected to the rev counter, the needle is rising as it's seeing a voltage, maybe faulty alternator ??

As for the click, I'd check and re-make off the battery connections, to both starter motor and engine block...........

 

[vatco]

Seen this happen with other vehicles sometimes

The panel and everything else gets it's initial 'spike' and then nowt result often electric gauges etc behave bery wierd

Pay particular attention to earth links rtc and as already said check battery terms and ign switch

 

[rayf3262]

Assuming the online manual is roughly correct for your TDI then:

Manual page SC-24 shows the alternator wiring:
The rev counter gets speed info from the ECM, which is derived from the crank TDC sensor. There is no tacho info from the alternator, only the charge indicator lamp.
The tacho anomaly may well be caused by a poor earth connection though.

Manual page SC-14 shows the starter wiring:
You should be able to connect the "B/W" (E114), (103), (M45) wire to the battery +VE terminal and the engine should crank over (but not start)

If it does not crank well, or at all, then as has been suggested look at the condition of ALL of the connections to/from the battery including the earth bond to the chassis, fractured cables, poor crimps etc.

If you have you have a volt/test meter? I can make some other suggestions.
Ray

 

[ocelot]

Assuming the online manual is roughly correct for your TDI then:

Manual page SC-24 shows the alternator wiring:
The rev counter gets speed info from the ECM, which is derived from the crank TDC sensor. There is no tacho info from the alternator, only the charge indicator lamp.
The tacho anomaly may well be caused by a poor earth connection though.

Manual page SC-14 shows the starter wiring:
You should be able to connect the "B/W" (E114), (103), (M45) wire to the battery +VE terminal and the engine should crank over (but not start)

If it does not crank well, or at all, then as has been suggested look at the condition of ALL of the connections to/from the battery including the earth bond to the chassis, fractured cables, poor crimps etc.

If you have you have a volt/test meter? I can make some other suggestions.
Ray

I sit corrected....................

 

[zippy656]

I sit corrected....................

and like me learnt some thing too

 

[rayf3262]

I sit corrected....................

Hey Guys, I'm new here and don't wish to p*ss on anyones parade..just trying to help where I can,.. electrickery is my thing..:thumb2

Assuming it does not crank over well by connecting the starter solenoid directly to the battery...

Connect one terminal of a meter to the batt -VE term. and the other to the starter or engine and operate the starter.. you should see no significant voltage when cranking the engine, if you do then its likely a bad earth connection.

Similarly, if you connect a meter between the batt +VE term and the "big + connection" on the solenoid you can test the integrity of the starter motor feed in the same manner.
These simple tests can save a lot of crawling around in this cold weather...

In a nutshell, I believe that there is a poor earth connection somewhere. When the IGN is switched on the glow plugs will be pulling significant current.
If all of this current is not returned by the ground wiring from the engine block back to the battery -VE term then it will find its way back via all sorts of paths which could easily result in the tacho doing odd things.

Be interesting to know if the tacho position changes if the glow plugs are off/disconnected.


Ray

 

[DEE]

Try turning ignition very slowly as a faulty ignition switch (seperate from ignition lock) can cause the click you describe.

Jim T

Iam with this one. common fault all right. As the man say,s turn the key very slowly not to far and she may turn over.