MY Tracker &  Sidekick  OBD2 (only)  C.E.L. PAGE  Check Engine Lamp.       
1996 and newer (USA) if your car is older , hit the home button above.
Vehicles outside USA my be different, vastly different.
Canada cars went to OBD2 in 1998. (many folks in Canada drive USA cars, look under hood for truth)
Best rule of all, "Ignore the lamp and SCAN it" In fact even better, drive , scan and log it.
The CHECK ENGINE LIGHT GLOWS RUNNING? (aka. SES, Service Engine Soon, Engine lamp, trouble lamp, me check lamp?)
First look for the 16pin DLC connector above your right knee, if not there, you must not be in the USA.

 (All USA 1996 and newer cars, you need an USA STANDARD OBD2 scan-tool/reader to pull the DTC errors) 
 
What are DTC Diagnostic Trouble Codes?   For sure, the correct year, FSM , covers each code and how to solve it best.
All mechanics call it the MIL lamp, Malf. Indicator lamp.
Offsite DTC page 89-98 96  USA ECU DTC'S
 96 Canada ECU DTC diffs.
96, 4Speed Tranny DTCs
 The real FSM 96 DTC My 99 to 04 DTC V6.
        
 More Real actual Suzuki  1996  DTC codes (off site)!

The Check Engine Light, is glowing while driving? Some times marked SES (Service Eng. Soon).
I will call it  a "CEL" from now on. (aka: MIL or SES  to mechanics)

This page is for the Engine lamp and is NOT for the Anti lock Brakes, or Air BAGs (called SIR) The are separate systems and there have own  tools.
In 1997 they add the bad A/T transmission DTC errors, P07xx and what not.  Prior to 97', the TCM has its own jumper plug and 2 digit codes. TCM is the 4SP tranny brain.
See a full scan of my ECU here step by step , looking for odd indications.

USA Cars 1996 + and newer, need a OBD2 code reader or a standard USA scan tool.   I use their wifi tool and the Palmer upgrade.
I highly recommend Palmer products full scan tools !

At the risk of making general statements in the  face of huge complexity , I hold my nose and say.....
If your car is a  96 or newer, just buy a scan tool with "CAN" buss features and it will work on all USA cars now and in the future.  Newer cars use CAN Buss.
They many types;  for as low as $9 at fleabay for a USB interface. & (Dedicated hand held, Android powered, PC of any kind, USB,wifi, Bluetooth and many others) I Have one of each.
I even have a OBD2 simulator now....(the legal kind, see my hacks page)

OBD2 code readers can  only read DTC error codes and can not look at sensors or live data streams. Code readers can reset the CEL, as can scanners,
Cars built for out side of USA market generally,  may  not use OBD2; until 2001 or 2006 , depending on the country. 2010 in China?

Some cheaper scan tools (readers) only support a partial OBD2 interface standard, avoid them.
There are some older scan tools, that do not support, all line level inputs. and will fail.  The cheap ELM327 tools all work. As cheap as $9 (and a relic USB laptop)
Make sure it has the features you demand, the OBD2 Fed spec. only defines a minimum level !   If you demand more, shop and find it. YOU WILL !
If you have other new cars, the best tool is one that does the full factory codes too,for all cars in your garage.  CAN buss.
If you have a Ford, Chevy or Mazda, there are nice, factory scan code options offered by the software makers.
The best scan too, might be the one that supports all lines levels seen here, (ISO and SAE) seen here on those 16 pins.
The worst tool, is probably the tool with only 3 wires in the connector "VPW" only? (look)
Here is my GEO, the mandatory pin 7. ISO-9141-2  (the next year, Suzuki switched to SAE-J1850 PWM. pins 2 and 10 used)

A good hand held is here. I use a  model 3100.
To pull the codes on any 96+ car, you only need to:
Pre-condition, KEY OFF:
  • Buy , rent ,or barrow a code reader , or better, a full scan tool.  Code readers are near useless for most service issues.  DTCs codes only !
  • Find the 16 pin, OBD2 jack (DLC) near the steering column, above your knees.
  • Plug in the scan tool or reader .
  • Read the book that came with said reader. (needs batteries?)
  • Turn on the scanner or reader . Follow books rules.
  • Turn on the ignition last. (no need to start engine, yet, but you can)
  • Press the SCAN button on the reader.  (if you get COMM failure , look for a blown fuse that feeds pin 16, on the DLC)
  • A good reader, can read as a minimum just key on the Monitor status, DTCs stored, DTCs pending.
  • A good reader can reset the DTCs stored in memory.
  • If  it is a  full  scan tool , you can even see the TPS, and ECT  values, live, with engine not started. Pin 16 must be hot, and CEL glowing ,not running!
  • I mention this so if there is trouble , you know it before you start the engine.   (A 96 Ford, is an other matter, just key on)
  • For more details see the next link below.
With a real scan tool and laptop, you can scan and plot any sensors or group of sensors and drive and log data to your hearts content.
This tool, can be instrumental to finding intermittent sensors.
The Power of OBD2 is only limited by your scan software and techniques.  Vastly superior to any previous technology.

Look up the DTC's using my links or the FSM for your car.
If you need help diagnosing the DTCs , then post to the forum.

Post your Thrown DTC's  here , on the forum and get help:
To RESET the DTC codes in ECU memory ,  you can:
First write them down, and log them.

Pressing RESET on the scan tool or reader !  Best.
or
Pulling the DOME or Tail fuse.  (out  for 1 to 2 minutes then back in)
No need to pull battery or kill vehicle alarm system , or remote start or de-program the radio. (assumes the car is wired correctly)

Reset the ECU and see if the codes come back, if they do?, they are REAL.
or
OBD2 can AUTO reset corrected errors after 40 cold starts of the engine,  i'd forget this feature, it is mostly useless to mechanics.
1996 to Present, OBD2 Cars in the USA, (1998 or newer in Canada)
See more OBD2 methods here.
In the USA , the USA EPA mandated OBD2 level EFI systems , this was a radical departure from the old system.
The EPA and SAE.org, invented OBD2, it's a USA invention. (others copy it, or rename it, but is our idea and creation) "EOBD 2001 or JOBD,etc are but clones"
Key, points.  (watch out , real Canada cars do not set the CEL glowing for Misfire or EGR failure, so use the scan tool up in CANADA to see the truth)
  • DLC  is now under dash in all cars, 16 pins, and near steering wheel.  No more hunting all over car. No more Suzuki moving it about, for funs and giggles.    NO MORE NAG switch.!
  • No more flashing , CEL lamps to obtain DTC errors allowed (it does do a double flash of CEL, if you are cooking the CAT to death (not in Canada E28 cars)
  •  No more looking for Suzuki scan tools (OBD1) that are not sold in any stores.  ( a true blessing )
  • You must use a standard, but cheap scan tool to read DTC errors,  and live data. , you can in fact buy a scan tool today for $9 whole bucks.(2013) (using any USB Laptop PC)
  • OBD2 now has many newer smarter tests, for the EGR and EVAP systems, and for detecting too rich and too lean AFR (air/fuel/ratio) mixtures. (extensive updates)  really useful to any mechanic.
  • Up to 13 new monitors.  ( a monitor is a test, it runs full time or runs just  once each driving cycle.
  • You can now reset stored, DTC codes and the CEL lamp to off , via a simple scan tool command (push button)  DTC means Diagnostic Trouble Codes,  or errors.
  • The big down side, is you now can fail  USA smog testing, if the A/T transmission shows faults.  P07xx codes, up to 10 tranny codes here, can fail you, just in 1996 alone.
  • The up side, is that in most states, they pass your cars smog test , just for having the CEL not stuck on.  (few minute glance and you pass)  Saves time and cash over the life of car. (P.R.of Calif, is different)
  • If you remove (evil) the CEL lamp, all scan tools, can see that you did, and shows the status of MIL/CEL, so you will not fool anyone... In fact, this is one of the smog stations first checks.
  • Newer cars (not Sidekicks) OBD2 shows the scanner, that you have the correct ECU in car, for your VIN and can even stores driving habits! (2005 + years) 
  • OBD2 really does reduce maintenance costs greatly and smog station testing (and your fees for same) greatly. For the life of the car.  (it does add up to less costs and less down time)
  • If you drive a car with the OBD2 scan tool connected, you can see just how well the EFI is working , in real time. eg.   A full scan of a 1996 OBD2 Suzuki engine.
  • OBD2 added Misfire detection on a cylinder by cylinder basis too, a very powerful tool in any mechanics hand.  (with added, new crank sensor)
  • Vastly better Oxygen sensor tests, it can even find a  dead Oxy. heater.
  • Factory scan codes, all makers of cars can extend the Federal standard codes @ P0xxx , using new P1xxx or P2xxx codes.  FORD and GM have many.
  • The ECU now can even warn you of a slow or bad, coolant thermostat. P0125.   Even too lean or too rich warnings...P0171/2  !  way smarter ECU.
One bad thing, most car parts sellers, get way rich,because owners think the ECU tells them ,what parts are bad (sic), they then guess and guess wrong, and bingo the parts guy is rich. Gravy for them....
Why do you think so many stores, offer free scans of your  car?,  they are getting rich faster !, and now you are in their parking lot,  BINGO, Ching Ching,  (no deposit , no return)
If you can't do the tests, find a mechanic "ASE" or go broke on wasted, thrown parts. (it is your cash, my comments are to folks, that work hard for their money)
Question, why not just pay the ASE mech. for diagnostics only?  then you buy the parts and fix your own car..
Let him do his craft, he is good. He will  not guess. or waste parts.  (He might ask you to tune up the car, after all, most never do....)


Where is my DLC:?

The  DLC photos, rules and locations, are here  (Suzuki loved to move it around for fun?) (all years )

Smog tests do vary by state , and here are ways  to pass it, no hype or magic bottles of liquid, that guarantee passing and don't.

DANG ME !, I can't pass my silly smog tests.



In Canada OBD2 started in  1998.  (other countries OBD2 start year? 2001, 2006?)

My OBD2 ECU/ECM tells me my CAT is bad.  Bah !  Read this first, if your mechanic don't understand these words, fire him. ?P0421?
A new CAT at Suzuki can be $1300 installed, or more....  don't let them guess.  "Catalyst converter TWC"

Do not go to the smog station, until the Red boxes below go GREEN.

The below chart, is non Suzuki car.
Our car, has most of the "not supported", as supported.
This is just  a sample photo below.  (use your scan tool to see the truth here)
The first OBD2 cars have a minimum of 9 monitors, today 2005+ it's 13 minimum.
Warning, 1996/97 Sidekicks/Trackers are listed at the EPA as having a 1 faulty readiness monitor (fails to clear). see page 28 for this discovery.
Some states know of this fault , others not.  This can be a pit fall for you.
They (EPA) didn't say which test, fails, so the smog stations are authorized to allow just you to have (normally) 3 monitors, not complete.  (or 4 if 96/97 year)
This is because the ECU is faulty those 2 years. and 1 more not complete is allowed.
(EVAP monitor, is the hard one to complete, at 20 minutes long and the  gas tank can not be full.)
Comprehensive test ,passing means the sensors on the car did not fall off or short.







TOOLS:
  • Most NEW  tools for OBD2 sold in USA support all 96 and newer Suzuki's cars. and light Trucks.  all 4 communications levels too. Including "CAN" bus.


JARGON:

rev: 22  ,  added example link.
 
Edited: 8-30-10