P1706 code engine light on +no reverse light still.... after changing the switch and light bulb

Hi all,

On my 2005 k12 1.2 sport daily, recently the reverse light stopped working and I want to get this fixed,
Did the usual fault finding, changed the bulb, got a new aftermarket reverse light switch, replaced it under the car by the gearbox.

After changing both of these, the engine light stayed on and continues to throw out a P1706 fault code, I am a bit baffled to what else it could be, anyone had a similar issue before with their k12 on here. I would be grateful for any advices / pointers for a fix on this issue.

Thank you :)
 
not yet, i will also check this thanks. what could it be if it's no / voltage to the bulb? where should i be checking as well
many thanks
 

frank

Club Member
usually you check for a live at the switch, but yours is probably canbus tho, which is more complex and wont show a voltage until you apply a load
 
hmm, ok thanks for your advice, what do you think is wrong with this in this case...
i will jack the car up and clean up the contact point when the weather is better lol

will also check for voltage may at the bulb side with the ignition on reverse gear in.

i suddenly lost the rear wipers as well the other day. unsure what is wrong. now the rear wipers will not function too
 

John_D

Club Member
Radio Code Guru
hmm, ok thanks for your advice, what do you think is wrong with this in this case...
i will jack the car up and clean up the contact point when the weather is better lol

will also check for voltage may at the bulb side with the ignition on reverse gear in.

i suddenly lost the rear wipers as well the other day. unsure what is wrong. now the rear wipers will not function too
Rear wiper fault on the K12 is usually one of two things, firstly as it's switched by the BCM (Body Control Module) disconnecting the battery for a few minutes should re-set it (and may well cure your reversing light problem as well as this is also BCM controlled). That gets the easy fix out of the way... The second potential (and VERY common) fault on the K12 is damaged wiring in the rubber 'elephants trunk' between the top right corner of the car body and the tail gate. DONT, as many do, split the rubber trunk for access, it is possible to unclip it from the body and/or tailgate and roll it back to get access to the wires inside. The wires are wrapped in a light foam like tape, do not be fooled into thinking that there is nothing wrong if the tape looks complete and undamaged, I wasted a lot of time assuming this, when the wire to the boot release on mine broke. :mad: I have so far cured the rear wiper and reversing light problems on my K12 by doing the 'hard reboot' of the BCM by disconnecting the battery and cured the tailgate lock problem by repairing the wires in the elephants trunk, though as there were several other wires there frayed and potentially shorting out I almost certainly cured several other faults, at the same time, before they manifested themselves. (I actually cut the loom where it leaves the car body and added a short repair section, soldered and individually insulated with heat shrink tubing, then fed the excess loom back into the car body before clipping the 'elephants trunk' back in place.....
 

Mika The Finn

Site Supporter
Rear wiper fault on the K12 is usually one of two things, firstly as it's switched by the BCM (Body Control Module) disconnecting the battery for a few minutes should re-set it...
John, before disconnecting the battery for a few minutes. Was it practical to switch stereo off? In order to to keep it functional and not end up asking radio code in various threads? :unsure:
On my Micra keyless acces lock/relase button on trunk lid has stopped working. Need to disconnect battery, hoping it would fix it...?
 

John_D

Club Member
Radio Code Guru
John, before disconnecting the battery for a few minutes. Was it practical to switch stereo off? In order to to keep it functional and not end up asking radio code in various threads? :unsure:
On my Micra keyless acces lock/relase button on trunk lid has stopped working. Need to disconnect battery, hoping it would fix it...?
In my experience if the radio is turned OFF when the battery is disconnected the lock code stays remembered for at least one minute with no external power, any longer than that you are in uncharted waters.....
If a hard reset of the electronics, by disconnecting the battery does not cure your woes then I think that you need to examine the wiring between the body and the boot lid as I explained earlier.....
 
thank you very much for your help guys, I am going to try reset the battery ! dont worry I have my radio code! its 1283 if this works for any one else :)
 
hopefully not the wiring because I am not good with electrics. mechanical stuff I am much better with lol will let you know if this fixes both these issues.
 
my rear wipers is up and running again ! thanks for the advice :) discounting the battery to reset the BCM worked. so my wiring in the boot seems to be in tack...

still no reverse light and there is no voltage at the bulb connector. the reverse light switch is new i fitted that last week... what else could that be and where should i start looking at for a fix?

thanks again for the help guys!
 

John_D

Club Member
Radio Code Guru
According to the 'Haynes Book of Lies' the reversing light is earthed through the rear light body and fed with 12 volts directly from the reversing light switch on the gearbox OR in the case of autos, a contact in the 'auto transmission selector switch'. Both of these switches get their power from the same source, fuse number 50, which is fed by the ignition relay.
Fuse 50 (which is rated at 10A) is located in the 'Intelligent Power Distribution Module' (IPDM) , which is located under the N/S headlight (and is a bastard to get to, unclip/rotate to check the fuses). Coincidently the ignition relay is fed directly via 'Link D' of the 'fusible link holder' on the battery +ve connector. The 'ignition relay' is located in the IPDM and as it appears to use the same output feed of 12v to the (amongst other things) the fuel pump relay, we can safely assume that there is power, at least up to the live side of fuse number 50. The power out of the IPDM, from fuse 50 is via pin number 36 on the connector block, which should be an orange wire. The same orange wire then goes directly to the reversing light switch on the gearbox. So first thing to do is check that, with the ignition on, there is 12volts on the orange input wire on the gearbox switch. If Haynes is to be believed both the in and out wires on the reversing light switch connector are orange, so there should be 12volts on one of them, with the ignition on and the car in neutral and 12 volts on both of them with the ignition on and the car in reverse. I fthere is no power to either, with the ignition on then the fault lies with either the wire feeding pin 36 on the IPDM or fuse 50 itself. If power comes out of the reverse switch when you do the checks explained above but no volts appear at the rear light cluster, then you have a continuity problem with the orange wire between the gearbox switch and the rear light , reversing bulb feed....I assume that you have a suitable multimeter?
 
i will have to check again, FYI the Check Engine light on the dashboard has come back on, and same error code P1706.
i will follow your guideline for the fault find and hopefully can identify the issue.

thank you very much for your help, very knowledgeable and helpful. :)
 
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