[threchka]

2003 nissan pathfinder le, battery died, changed, since then the 4wd indicator light system does not light up except at startup. The 4wd warning light is constantly on. 4wd appears to be functioning.
Thank You

 

[MattyDK23]

Whenever the 4WD diagnostic light stays on, the 4WD indicator lights will not come on. That's normal.

If the battery was low/dead for a long time, the self-diagnosis memory in the Transfer Control Unit may have been erased. If this is the case, driving around for a while should give it enough data and the 4WD light should go out.

If you have an ODBII code reader, you can check if there are any codes stored in the ECU. There is also a diagnostics mode you can go into for transfer case issues:

1. Warm up the engine. Turn it off.
2. Turn the ignition switch on and off at least twice, then turn the ignition switch to off.
3. Shift into park.
4. Turn the 4WD selector to Auto.
5. Turn the ignition switch to on. Do not start engine.
6. Is the 4WD warning lamp on? Continue if no.
7. Shift into reverse.
8. Turn the 4WD selector to 2WD, Auto, 2WD.
9. Shift into drive.
10. Turn the 4WD selector to 4H, Auto, 4H.
11. Shift into neutral.
12. Turn the 4WD selector to Auto.
13. Shift into park.
14. The 4WD indicator light will come on for 2.5 seconds, then go out. It will then flash a series of times to represent a one or two digit code, with half-second delays within a number and 1 second delay between numbers. e.g. to represent the code 23, it will flash twice with 0.5 seconds between flashes, wait a second, then flash three times with 0.5 seconds between them. If there's a number, reply and I'll look up the code for you.

If the light just flickers with 0.25 second delays, the memory is the problem and just driving around should fix it.

If there's no light on, either you did it wrong or the one of the PNP (park/neutral position) or 4WD switch circuit is open.

 

[threchka]

flashes a 4 digit sequence, 6, 17, 22, 23. 4wd system lights are on, 4wd warning light not on now.
check engine light on now, is there a way to read without code reader?
thanks for your time, i appreciate it.

 

[MattyDK23]

If the SES light is on now, I'd pull the codes, since it might give an insight into what's happening. That said, if the 4WD light is off now, things may be OK and the SES light might go off after starting the Pathy a few more times.

An OBDII code reader can be had as cheaply as $50 - $100... a good investment for a DIY mechanic, especially since it works on all vehicles '96 and later.

The codes from the service manual are:

Code 6: "[Appears] If unexpected signal is detected because of ABS wheel sensor
malfunction or communications error between the vehicles. Check ABS wheel sensor signal circuit diagnosis."

Code 17: "ABS operation signal circuit is shorted. Check ABS operation signal circuit."

Code 22: "[Appears] If VDC operation signal is being input because of VDC malfunction
or communication error between the vehicles. Refer to VDC C/U diagnosis."

Code 23: "[Appears] If TCS operation signal is being input because of TCS malfunction
or communication error between the vehicles. Refer to VDC C/U diagnosis."

 

[mwacker]

My 4WD light was on so I took it to the Nissan Dealer. They said the 4WD was functioning fine and that it was possibly the line pressure switch and it would probably cost at least $1700 to fix it, but it's probably fine. In my experience it was functioning fine.

Didn't trust their diagnosis seeing as they could have at least read the computer code and told me what that was saying. Anyway i followed the procedure above, I wasn't able to catch the codes the first time around and my battery happened to die. When I jumped it the 4WD trouble light was off and the dash lights are now functioning fine. Did I just reset it?

As I mentioned before the 4WD is fine during hunting season here, so I'm sure of that. The only thing i notice is when i hit 30-45 mph I have a slight vibration in 2WD, and a quite noticeable one in 4WD.