Ignition unit

I think the ignition unit on the back of the steering lock of my 1990 90 has gone duff.No power getting to solenoid. Can start motor with wire direct from starter to a touch on the battery.
How much trouble to just change the unit? Or am I better off changing the whole steering lock?

Is the starter relay working

No noise/click when key is turned.

Have you had a look at the switch? Wire might have fallen off.
Simple job to change the switch just fiddly, quite cheap too under a tenner last one I got but that was yrs ago.

tottot said:

No noise/click when key is turned.

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That doesn't mean that it has to be the ignition switch, if the relay coil fails (or the wiring to it) you won't get a click either. Quick check with a meter on the switch will let you know which way to look

Has 1990 year got a relay?
Dunno, but good point.

Flossie said:

Has 1990 year got a relay?
Dunno, but good point.

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Good point about your good point

Although now a 200 my 90 was originaly a 19j [ one of the last made ] so I do not think it has a relay, the ignition switch has had an intermittent fault for the last month. Taking the key out and trying again has got it going until now. Not got a look at it yet.

tottot said:

Although now a 200 my 90 was originaly a 19j [ one of the last made ] so I do not think it has a relay, the ignition switch has had an intermittent fault for the last month. Taking the key out and trying again has got it going until now. Not got a look at it yet.

Click to expand...

My 90 also started out as a 19J. The last owner changed the ignition key as it was different for the 200tdi....
Don't know how true that is but it certainly has a new ignition key

tottot said:

Although now a 200 my 90 was originaly a 19j [ one of the last made ] so I do not think it has a relay, the ignition switch has had an intermittent fault for the last month. Taking the key out and trying again has got it going until now. Not got a look at it yet.

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Does the key turn easy enough?
If it does the barrel will be ok. The switch itself does all the functions and is turned by a peg from the barrel. IMHO the wiring direct to the glows from the switch or the switch itself is not man enough to handle the current. I found burnt and melted wires from the switch to the glows during the restoration of my 110 nad (now a 200 TDI) so I installed a relay to take the load of these components. I suggest you remove the cowling and check out the 2 heavy cables /large terminals (brown iirc) for heat damage. If they are ok replace the switch , 2 screws hold it to the barral, fiddly to do, or tap the security bolt heads undone and remove the whole thing for better access. Make a note of wire positions!
If the wiring does have heat damage, cut it all out and rewire preferably with a relay to switch the glows , I mounted the relay behind the fuse panel.
If it sounds daunting it really isn't!

My Old Landy said:

My 90 also started out as a 19J. The last owner changed the ignition key as it was different for the 200tdi....
Don't know how true that is but it certainly has a new ignition key

Click to expand...

The pre 200tdi had the hold to glow position on the key just before crank, later models used a timer relay with no hold for glow position on the switch.

Flossie said:

The pre 200tdi had the hold to glow position on the key just before crank, later models used a timer relay with no hold for glow position on the switch.

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Thanks for that, I am learning every day!
This is what I love about this forum, everyone pitches in to help.
I hope the OP gets it sorted

Thank's for the info Flossie,my 90 [ had it 25 years and the ignition unit is one of the few parts I have not had to attend to in that time ] still has the original hold on the glow position switch and that part still works fine just no power to starter.
Just wonderd if it was best to change the whole thing or only the ignition unit which I recon you have answered.
Starter is jury rigged to a switch under the bonnet for now and have sent for an ignition unit. Will investigate when it arrives Thanks again,cheers.

Change the whole lot. It's easier

Don't worry about installing a relay etc for the 200TDi glowplugs - it's doesn't need pre heating unless you live somewhere very cold.

Not botherd about a glow plug relay,If I need them they are available on holding the key at the right spot as per 19j engine.

Sorted,new original type ignition switch fitted in situe.No damage to cables. As you say Flossie a bit of a fiddle,not a job for someone with dinner plate hands.

Glad you got it sorted!!