Pathfinder R50 (2001) interior light not working when driver side doors opened

[mrmagicbg]

I have a second hand Pathfinder R50 (2001) XE where I have this weird problem with the interior light. It will come on when passenger side (RH) front and back doors are opened but will not come one when I open the front or the rear driver side doors (LH). Door switches are OK - tested. Also it is confirmed by the fact that the indicator for open door lights up on the dashboard when I open one of the doors and it also beeps at me when I leave the headlights on or the key in the ignition so door switches are out of the picture for me.

There was a discussion online where some Gentlemen suggested the smart entrance control unit could be bad so I bought second and unit and replaced it but I still have the same issue. I inspected both units for bad/burned solder joints, bad components, etc. and all looks fine.

Now chances are either I bought second hand smart entrance control unit with the same problem or it is something else ...

Any of yo Gents came across such issue in the past?

Attached are some pictures of the smart entrance control unit my vehicle model uses (I took it apart for tests)​

 

 

[hawairish]

Have you checked the FSM's component description by chance? It'll tell you all the scenarios and when power or ground is supplied, and to which terminals. It also has the wiring schematic. You should be able to probe them.

 

FSM's are available here: http://forums.nicoclub.com/pathfinder-qx4-general-information-and-q-a-t549378.html

 

Judging by the system description (check the EL section for "Interior, Spot, Vanity..."), there are multiple grounds for the LH FR switch when the door is open. Might need to do some continuity checks.

 

The FSM also (amazingly) has several pages dedicated to testing the timer circuit...probably not related, but I'd take a look at some of the individual steps.

 

Good luck, and welcome aboard.

[mrmagicbg]

Hi,

 

thanks for the prompt response. I went through the ground points checks already but your suggestion of doing continuity checks on the wiring got me thinking so I went to check some of the wiring again and this time I pealed off some more insulation tape on the main bundle of cables going to the Smart Entrance Control Unit (like 1 or 2 more inches) and I found that some IDIOD had altered the wiring (like 2-3 inches back from the connector) and then masked it very well with insulation tape - it looked as if it was coming out of the factory

 

what else pointed me to start checking the wiring again was that after I decided to re-do the tests I did in the past I noticed something very peculiar ... when I open the driver side doors I get the open door indication on the dashboard lit (but no interior light) but when I open the passenger side doors I do get the interior light and guess what no indication on the dashboard that the doors are opened. To me this indicated someone did something to the wiring - perhaps the old Smart Entrance Control Unit was shot and someone tried to work around the problem by re-wiring the interior light ... obviously he didn't know what he was doing

 

Anyway - I will pull all the wiring out and re-wire everything as it's supposed to be (will follow colors and schematics), will do it on a weekend as it seems it might take few hours

 

Thanks again for help.

[hawairish]

I know you've ruled out the switches, but if I'm not mistaken, the LH and RH switches are actually different part numbers. Have you tried swapping any around?

[hawairish]

Actually, just noticed that there's some conflicting info regarding the switches in the parts diagrams I use. The fronts are the same, but different from the rears (rears are the same). Maybe something is still crossed up?

[mrmagicbg]

Yep - tested them, all is well with the door switches, on my vehicle both read doors + the from passenger side switches are the same, only drivers side switch has additional wiring (as it is supposed to control more I guess)

 

I will re-check them together with the re-wiring I'll do this weekend and will let you know

[hawairish]

... when I open the driver side doors I get the open door indication on the dashboard lit (but no interior light) but when I open the passenger side doors I do get the interior light and guess what no indication on the dashboard that the doors are opened.

 

For some reason, this stood out the second time I read it. I feel like I had this exact problem on my 98 Frontier once, but it didn't have any light control whatsoever (and only two doors). I can't recall what I did to fix it, let alone if it really happened. I remember once messing with the door jamb switches on the Frontier, but I can't remember why...might have been to wire an alarm to the switches.

 

I may be getting things crossed up because I've actually been looking at the door switches recently because of mod I just completed. But I swear, I had some odd problem like that once.

 

By chance, is there an aftermarket alarm tied into the door switch as a trigger??

[mrmagicbg]

Yep, there is but it was installed recently (2-3 months ago) and I have the problem since I purchased the car - more than an year now so I don't think it is related. Also the alarm that was installed is controlled by the original car key and integrates with the NATS system so it is hooked up to the main bundle of cables going to the Smart Entrance Control Unit and did not require any modifications to any other parts of the car. What it does is when the car is locked it triggers the horn and has a shock sensor in case someone hits the car or breaks the glass.

 

I will try to rule it out when I'm doing the re-wiring this weekend, I'll disconnect it and test w/o it, but I'm sure it won't make a difference