License plate lights out on 2002 SE - clueless
 

Hello,

My first post, glad to find this site. I own a 2002 Maxima on which both license plate lights have gone out. I found this out when a cop in a speed trap town nearby pulled me over this evening and informed me of this. (Heck, I don't even think about those lights!)

I've done the following due diligence:

1) Unscrewed the right hand light unit, unplugged it from the harness, and opened it up to find the 5W bulb with the filament intact which an ohmmeter says has continuity. So it's not the bulb.

2) I checked the wiring harness/connector to the bulb module and when headlights are on it has no voltage.

3) Pursued the issue online and found references to a tail light fuse being shared with the license plate lights. I checked those fuses (in the under-hood box) and nada - all were unburnt/good. I checked most of the fuses labeled as being light related.

I found this thread here on this site:

https://maxima.org/forums/5th-genera...t-working.html

I downloaded that manual and checked it out... I see the wiring diagram but I'm absolutely clueless on the legend of the diagram as well as whatever a "Stop and tail lamp unit" is or looks like.

Can anyone provide any pointers? Or should I just take it to a shop? I'd be grateful. Thanks.

No, don't take it to a shop, you can fix this yourself.
These suggestions should get you going:

• Download the EL section of the FSM from the link on the 2nd line in my signature below.
• The description of the "Parking, License and Tail Light" subsystem starts on page EL-65. Just peruse the description and move on to page EL-72.
• Page EL-72 has a decision table that will help with your trouble diagnosis. I assume the 2nd row of this table describes your problem. If so, the last column tells you how to proceed. In this case, there are six steps that you should try in sequence.

Hope this helps.

Hi @maxiiiboy - thanks for the encouragement. I found the section and the page you mention.

Here comes the bombardment of further questions:

One major problem I have is relating the instructions here to physical components and locations. Where would the "smart entrance control unit" be located?

How do I check a (tail lamp) relay or any relay for that matter?

Check lighting switch - the headlights work so I'm unclear what other switch would be involved.

Smart entrance control unit?

Does the manual have illustrations of these things?

Thanks...

The short answer is: the SECU (Smart Entrance Control Unit) is located above the ECU; see the picture on pg. EL-342 (this is for my car, a 2k Maxima).
The long and more meaningful answer is:

• Download yourself all sections of the FSM for your car.
• To find things, always start with the IDX section. For example, if I want "location of electrical units", the IDX tells me to go to EL-340 (section EL, pg. 340, again this is for my car).
• Read - or at least peruse - the GI (General Information) section. It will tell you how to read electrical diagrams, and how to check up electrical parts such as connectors, and many other things.
• Re. relays: Does it click, any burns .. ? Or, just buy a spare one and try, it's only $10 (here: https://www.rockauto.com/en/catalog/nissan,2000,maxima,3.0l+v6,1359222,electrical-switch+&+relay,tail+lamp+relay,3836 )

You should be able to figure out the rest!

The tail lamp relay is fairly easy to check because when you turn on the parking/headlights, the tail lights, the side marker lights and the license plate lights should all come on together. If you turn on the light switch and any of the above mentioned lights come on, the relay is working. If none of the lights come on, there are things besides the relay that could cause this. The tail lamp fuse is one of them.

If some of the lights come on but not others, you may have a wiring problem.

In the case of only the license plate lights, you could have a ground problem. First see if the red/blue stripe wire on the tail light lamp socket has 12 volts on it. If yes, then do a continuity check on the black wire to a ground that is not on the trunk lid.

Excellent easy to check suggestion, Dennis. Thanks. Also I appreciate Maxiiboy's continued help.

Ok, guys. I owe a report back.

Per Dennis' easy check for ground, I did so just now - the other evening I was working sloppy and apparently I didn't contact the terminals inside the harness plug.

Both bulb's wiring harnesses are getting 12V.

The bulb housing on the right side is intermittent. The right hand bulb came on, I reinstalled the housing, and it went out. I thunked the lens of the light and it came on.

The left hand bulb is flat out (no continuity.) So both sides had their own separate issues the night I got pulled over.

I'm very relieved it was not some control module or a $$$ wiring fault $$.

Thank you very much for the wisdom. Saved me a trip to the garage.

At Least $350 @ the Stealership....