Micra K11. All Indicators come on and stay on for several seconds.

[asimms]

Hope someone can help with this fault.
I've had this intermittent fault for about 3 years, where all Indicators come on and stay on for a few seconds then go off.

This can happen anytime and in any weather condition although it seems more prolific in wet weather, but it has also happens in dry conditions.
I can't reproduce the fault so all I have been able do is try a few things during the few second that it happens.
This is what I have tried:-
Switching on and off the hazard light switch.
Using the Indicators.
Locking and unlocking the doors from the internal door lock central locking mechanism.
None of these do anything to get the indicators to switch off.
When this fault happens the indicators are on solid, no flashing.

I have also checked the engine earth and the earth connection under the bonnet.

Looking at the wiring diagram I can't see a mechanism that would allow this to happen in regards to either the indicator switch or the hazard lights.

The problem look more akin to when you unlock the car using the central locking button on the key although the indicators can stay on for longer then when you do this. So my guess was that the issue is related to the central locking so I tried pressing the key door lock switch and this dose seem to make the indicators switch off. I then replace the battery in the key but still have the problem.

Despite having looked in the Nissan service manual I have not been unable to find any reference to the central locking receiver, it's wiring or location.
The problem is very intermittent and I can go many months without issue, or it can happen 2 or 3 times during a journey. It has also occurred whist on the drive before I have even gone anywhere, in fact it maybe before I have even started the car (not sure) where the key was inserted and the ignition switch set to the first position.

Any ideas on the problem would be highly appreciated.

 

[pollyp]

Sounds like a faulty Flasher Unit relay located next to steering column / central locking / fusebox

 

[asimms]

Thanks Pollyp for coming back to me on this.
Having looked at the wiring diagram I can't see this as a mechanism for this fault, since both the right and left hand indicators come on together. The flasher unit output feeds through the indicator leaver/switch so with this in the neutral position power should not reach any indicators. Indeed that is the reasons I tried operating the indicator leaver/switch when the fault occurs but it dose not turn the indicators off. In the case of the hazards lights where the flasher unit output would go to all indicators via the hazard switch, it would have to stick permanently on and also require an intermittent fault with the hazard switch. I checked and don't have any fault with the hazard switch (I even changed it for another one just in case).
The only mechanism that I know of that would switch on all indicators without flashing would be the remote locking (when locking the doors). Indeed pressing one of the buttons on the key (not sure which as it's hard to see when driving) is the only thing I've found that turns off the indicators when this fault occurs, and it dose this immediately. I have no idea where the receiver for the remote locking is and can't find any details about it. My thinking is that their may be a lose earth on it that may cause it to send a false pulse to the ECU (I'm assuming the ECU controls the central locking) but without any info on how this operates I can't say. I also have an issue with my own conclusion as I would expect the doors to all lock if this were the case and they don't! I do appreciate your response (and also the photos as it's a pig to get to the flasher unit so for reference they are very useful) maybe I've missed something so do please give me your thoughts. Thanks Alan.

 

[pollyp]

Ah yes, I just re-read your symptoms & restudied the diagrams again and it I think you're right.

Something attached to the indicator/hazard circuit (ie aftermarket alarm and/or central locking wired into the left/right indicator switch circuit) is sending 12v to both sides randomly, even if not commanded by the indicator switch or hazard switch.

Maybe the central lock unit or alarm unit is playing up, and the solenoid that's stuck ON is sending constant 12v to the indicator circuit, until that control unit is next disrupted.

I once had a failing alarm box do this.

Try eliminating the possible cause from the flasher circuit by unplugging the central locking control unit (behind the flasher unit under the dash) and see if the issue still happens.

If it's stopped, then it could be the central locking at fault.

 

[asimms]

Thank you, I've not found any information about the central locking control unit so I didn't know where it was or how it's connected. Taking it out sounds like a good plan. I also have a doner car so I should have a replacement one in that if it come to it. I take it this unit is what gets programmed for the specific key. I'm also betting that it's a pig to get to. If you have any information or can point me to any information about the central locking that would be much appreciated.

 

[pollyp]

On my prefacelift it's the big black box behind the flasher unit shown in my pic with the two plugs underneath it

 

[asimms]

OK, that looks quite big and tricky to get out! My micra is a late one (2001) so full facelift. I guess it must be in the same area. I'll have a poke around. Information on it seems a bit thin on the ground. I didn't spot any in the Nissan service manuals and the old Haynes manual has it in the wiring diagram (both the pre and facelift ones) but without showing any connection to the indicators. For the prefacelift the Haynes manual shows it as the deadlock unit (with two connectors) and for the facelift as the central locking control unit (with one connector shown in the diagram). Online I can only see pictures of the one you describe so I assuming they all use the same one but Haynes didn't bother to show both connectors in their wiring diagram. Best I'll go look !!
Thanks for guiding me in the right direction to find where it is, you're a star. Enjoy your Easter.
All the best Alan.

 

[asimms]

Yes, it is the same unit with two plugs and not so difficult to remove, Cheers.

 

[asimms]

Just to finish of the thread, I replaced the central locking control unit a few days ago and not seen the problem since. A quick tip for anybody doing this is to remove the cowling over the instrument panel so you can just about see the control unit. The unit is held in place by a 10mm self tapping bolt that has a pozidriv in the centre. You can just about get to it from under the drivers parcel shelf and undo it with a small spanner. Then if you remover the OBD socket you can just about get to the pozidriv with a long screwdriver to get it out.

 

[asimms]

Thanks again PollyP for your help.