TCS off and Slip light problem

[devnull1260]

Lately, the TCS off and slip light are staying on after I start my '99 Q45. Some times it will stay off if I simply turn off and re-start the car, but it has become more and more persistent. The car drives fine otherwise, I checked the forum, and found some info regarding "TCS relays", but it seems it only applied up to the '96 Q. There is no service engine light, does anyone have any idea what could be causing this?

[tmak26b]

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Lately, the TCS off and slip light are staying on after I start my '99 Q45. Some times it will stay off if I simply turn off and re-start the car, but it has become more and more persistent. The car drives fine otherwise, I checked the forum, and found some info regarding "TCS relays", but it seems it only applied up to the '96 Q. There is no service engine light, does anyone have any idea what could be causing this?

Pull the codes to get started

[maxnix]

How old is your battery and does it meet OEM minimum specifications?

Load test your alternator.

When I pulled the plenum the second time, I had the problem for a while. Reconnecting on the othe driver's side plenum connectors weemed to cure, but darn if I know which one. Might be the one behind the TB towards the firewall.
Modified by maxnix at 8:23 PM 8/17/2008

[devnull1260]

The battery is 3 years old, OEM, 8 yr battery. I recently had a problem with the evap purge control solenoid valve (service engine light came on) and replaced it, which cured that problem (another post you helped me with). I looked in the FSM for the troubleshooting guide for this symptom and it is about as clear as mud. I'll pull the codes and see what happens, I wasn't aware there would be a code to pull unless the service engine light was on

I read somewhere that if the tcs/off, slip, AND abs indicators are all lit, it is a sign of a bad alternator, but everything seems fine there too.

[qship96]

Genuine nissan/infiniti battery is only good for 3-3.5 years MAX, especially in HOT climate states......dont for a second trust the 84 month prorated warranty offered by nissan- it is just MARKETING to create repeat sales of batteries as you must purchase another battery from them in order to get your couple of dollars of warranty coverage{prorate}

[devnull1260]

I reseated all the connectors as suggested, and everything is functioning normally again, at least for now.

I checked the battery, and it is actually 2 years old, but you are right qship, i have never had a battery last more than 3-4 years here, no matter what the warranty claims. I get a pretty decent pro-rate though at 3 years on an 8 year warranty. It is not a Nissan battery, just meets OEM standards, it is an exide orbital battery.

[devnull1260]

OK, well that was short lived. The tcs off and slip light are back on, this time i pulled the code, it is p0325, bad knock sensor bank 1. Is this just a straightforward replacement or should I be looking for other causes?

[96Qowner]

No, I think you have some sort of battery/alternator problem.

It's typical for the ECU to throw odd codes when the charging system is funky.

[99q45t_vl]

OK, well that was short lived. The tcs off and slip light are back on, this time i pulled the code, it is p0325, bad knock sensor bank 1. Is this just a straightforward replacement or should I be looking for other causes?

I've had the same problem with tcs off and slip lights, and had to restart the car to cure it. Did not get any codes. My battery is new Interstate MTP-24P, so I guess, it's the time to check the alternator.

[devnull1260]

Strange you have no codes with those lights on. For what it's worth, I just ran my Q through emissions, with the knock sensor failure, and it passed with no problem. They even listed the PO325 code on their results sheet. At least I got that going for me.

i guess i will also have the battery/alternator tested. What a pita.

[qship96]

http://i259.photobucket.com/al...8.gif

A snapshot of Consumers Reports latest battery test for those in the market for a new battery....group size 34 fits perfectly with the g50 using the included snap on bottom tray that comes with the optima or platinum.

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Modified by qship96 at 5:45 PM 8/18/2008

[devnull1260]

I had the alternator, and battery tested. Both passed with flying colors, but i am still getting the tcs off/slip lights on, and code for knock sensor. Should I believe it now? Or is there something else I should check first? Or just ignore it?

[dodiho]

Devnull...I have had the same lights on for months in my '99Q....have asked all the Nico guys several times what else causes them to stay on when running...my battery and alt are both tested out good.....I wish someone would come up with a logical,rational fix for this instead of reading the Factory Manual--which can be as complicated as nuclear fusion studies.....my OBDII shows no codes but a bad o2 sensor which I will replace this weekend....and I live in hot central Texas.....my car has only 136,000 and I wanted to keep it another year or so....I have ordered some new coil paks to replace my original ones which should help fuel mileage..it has dropped from about 24 on highway to 19 or so....please let me know if you come up with a fix....just an irritating thing with all 3 lights on all the time.....

[maxnix]

.....my car has only 136,000 and I wanted to keep it another year or so....

....just an irritating thing with all 3 lights on all the time.....

So are you driving 100K next year?

All three including the Alt? Or CEL? I would still high load test the battery and look carefully at the alternator wave form. Sears or Wally ain't going to cut it. Take it to a specialty automotive electrical shop.

I think you are both being misled. Neither should every coilpack need replacement simutaneously.

[devnull1260]

Mine has 85k, so I am not going to replace the coil packs or plugs for a while. For me, it is the TCS OFF and SLIP lights that are on simultaneously, now more often, it has become less intermittent and more constant over time. I still get the P0325 code (right bank, knock sensor) with no engine service light. My battery was load tested, and my alternator tested (just VOM, no scope), but they remain lit. If it is the knock sensor, I certainly do not notice any difference in performance, acceleration, mpg, knocking, etc. I am curious though if there are anomallys showing on the scope, wouldnt that translate to fluctuation on the VOM during testing? This is an irritating problem, and it seems somewhat common, and elusive. If the alternator scope test passes, can it then be assumed it actually IS the knock sensor? Also, what are the consequences of driving it with a bad knock sensor anyway. I just passed emissions with the code noted on their report, but that is sure no guarantee I wont F up my engine....

[qship96]

Faulty Knock sensor NEVER illuminates the check engine lamp, just stores the code as you saw.Nissan uses crappy knock sensors,and almost every single nissan sooner or later develops problems with their knock sensors{I read the knock sensor code/problem is the most frequent code seen on all nissan vehicles}

Driving with bad knockers wont damage engine, it MIGHT produce a little less power, or lose a tiny bit of MPG, or you may feel no difference whatsoever....the good side to having the problem, if there is one, is that you can use regular unleaded fuel until you replace the knock sensors, as the ecu has greatly retarded ignition timing map to eliminate engine knocking since it cant rely on listening to working knock sensors for feedback.....using premium unleaded with faulty knock sensors is throwing away money for no reason!!!!

[devnull1260]

Thanks for the information qship, that is very good to know! They look to be a pain to replace, and sort of pricey, so I will just put it off for a while. Just for grins I'll have the alternator tested on a scope, but from what you are saying, its probably the knock sensor...

[maxnix]

As per my post in another thread, check the MAF connection carefully to verify it is locking and stable. Mine wasn't and started illuminating the TCS and Slip light and stalling badly weeks later.

[devnull1260]

I chaecked the MAF connector and it is ok. TCS/off and SLIP still illuminate.

One question, it seems to me that there is no possible way to change the timing map independently for right bank or left bank, so in my case, if only the right bank knock sensor is showing as failed, does the ECU just discard data from the existing, still good, left bank knock sensor? Or does it just say screw it and stick with the default timing map? Im not technical guru, but it would make sense that since the timing for left bank and right bank are dependent on one another, the ECU should still "honor" input from the existing, good knock sensor and alter the timing map accordingly... How does this work?

[Q45tech]

If either KS shows a code the ecu automatically switches to the protective equation and limits ignition advance degrading acceleration amd MPG.

KS are wear and tear items like spark plugs, relays, hoses, filters, liquids, brake pads, rotors, shocks and every one of the multi hundreds of rubber bushings and isolators.

Just part of the $20,000 in retail [MSRP] parts you will buy if you drive a Q long enough.

IMPORTANT to understand that early OBDII was not very good at reading codes on things beside engines and transmissions!

Technicans KNOW to go to individual auxillary computer [ABS/TCS and body control] to narrow down and find the reasons for lights.

THE FSM is designed for High School grads with at most 2 years of votech school and those with average IQ. Failure to comprehend is the readers fault. Since 27% of US have a college degree [dubious as it might be], what is lacking is the 2 years of practical votech experience.

[arunciks]

I have/had same issue with I30t 2000. Since I started the ignition and lights came on and my engine was all rattling. I knew one of the cylinders wasn't working.... I checked the coils while engine was tuning and one was lose and as soon as i touched it started to work fine... and after restarting engine the lights went off.

[Marshall206]

I have the same prob with the TCS and slip lights,

pretty annoying, but I also have major misfire so im gonna try to track down the bad coil first, but I think I need to replace my k/s and harness as well

[devnull1260]

My Q45 has the tcs/slip lights illuminated, but there is no problem at all with the engine or anything else. It has been that way for 2 years now. I have been doing regular maintenance and such, and so far have experienced no ill effect. I imagine as Q45tech said that my knock sensors are fried, but since it does not harm the engine, or prevent me from passing my emissions test, so be it. I really have not noticed any performance issues either. 100k soon, so i will be putting new plugs in, guess I will check the coil pack things then. Maybe new knock sensors too.

[Marshall206]

what should I expect to pay for k/s and harness?

[arunciks]

get the ECU cable of ebay .. like $20 connect to usb on the laptop and try reading codes. sometimes it might get stuck on the old problem issue..