SRS Module bad ?

Hey all,
Got a 04 Taco Prerunner V/6 and the air bag light is on constant since a couple days ago.
Does anyone know what road I should take without it killing the bank ?
Recenlty I have seen my ABS light come on at no specific time and on the next start up, it's gone.
I did clean the sensors in the front with Brakleen parts cleaner and have not see the ABS light come on since.
I'm wondering if the dirty speed sensors are the root cause of the airbag light issue I am now having. If it was, I again need to buy a special reader to reset the module ?
Local auto parts stores show no codes, but I don't think their OBD scanners do ABS or SRS system scans as I've seen that most scanners do not have that capability.
Should I purchase a scanner 1st off that does read ABS and SRS systems and begin there ?
Should I send mine out to be reset without doing anything else ?
I see there are company's that claim if I take it out, send it to them, they say it can be reset and reinstalled for under $50 bucks.
The part number for the module is 89170-04040.
The dealers want over $600 for a new one. $180 for a used one.
No crashes, just on my way to work, parked at work, put my emergency flashers on and when I looked down at the cluster, the airbag light was on. No crashes, no hard braking ob the way to work.
Just out of the blue,, any clues, suggestions ?

Where I work, I am able to park my baby in a bay and drive a company truck for work.
So when the flashers were tuned on and the light was seen, it was just so I can swap out vehicles without getting a ticket for parking on the street.
Broward County Jail right across the street from our building and them boy's don't want people stopping by their Jail/Courthouse !!

 

The ABS and SRS codes can't be read via ODBII for 1st gen trucks. There are procedures in the FSM (jump two pins on the diagnostic port, and then read dash light flashes) to get the codes- once you have the codes, the FSM also has troubleshooting flow charts.

Be careful with the ABS system in this partially working state. The ABS system can activate and modulate the line pressure which will make it feel like you can't stop.. and sometimes you can't if you're not expecting it. Immediately pop the shifter into neutral (or put the clutch in) and slightly lift your brake foot. Be ready on the e-brake if necessary. Now it a great time to make sure that your e brake is correctly adjusted.

The ABS and SRS systems don't interact, so the sounds like you have two separate issues.

For the SRS system- make sure you disconnect the negative terminal and wait a bit if you do anything with SRS modules or sensors.

 

On my 99, the airbag light was on when I bought it too. When I tore apart the dash to replace the radio, I unplugged pretty much every electrical connection I could find that seemed related to the airbag stuff and made sure the connectors were clean and put a tiny dab of dielectric grease on there, hooked everything back up, and the light has been out ever since. It might be worth trying something easy like that.

 

I just recently resolved this same issue on my 2002 PreRunner V6 and the fix was to replace the airbag control module.

My symptoms were the same as yours with the airbag light on constantly. Also, both cruise control and the horn worked which would suggest that it wasn't the clock spring. Like you, I first cleaned the SRS sensors near the front of the engine bay but that didn't resolve it.

I'm not totally sure what Andy01DblCabTacoma means by saying that SRS codes can't be read via ODBII for 1st gen trucks because I can tell you firsthand that I had a B1100 code that I was able to read with my OBDII scanner. If you are able to get a scanner that can read SRS codes, I would start there. B1100 indicates a malfunction in the airbag sensor assembly which made it pretty clear that the problem was with the control module (part 89170-04040). I also considered sending mine out to one of those services but, after looking into it further, it became clear that those are really more for resetting a module that was in an accident rather than fixing a faulty module.

I got lucky and was able to get a used module from my local junk yard from a Tacoma that was verified to not have been in an accident. Swapping my bad one with the used one solved the problem and I have been code/light free for about a month.

 

What year is your vehicle and what ODBII reader are you using?

Here is the official technique:



The FSM goes on to mention that there is a Toyota Hand Held Tester (which I am sure just automates the process). Maybe modern ODBII readers have implemented the same logic, but that is far from common, and not part of the ODBII specification.

 

Your OBDII scanner must be able to read ABS and SRS codes.
Like I wrote in my post, my local auto parts stores scanner read no codes.
I may unplug the module, clean the terminals, apply dielectric grease and see if that works as it worked for a members vehicle in a prior reply.
I also believe you are correct in regards to sending the module out to have it reset as mine was never triggered due to a crash. If the dielectric grease does not work, I will then search for a module. Thanks everyone for your input

 

Keep in mind, it's not the dielectric grease that's going to help you here. What's actually going on is that you should be disconnecting the harnesses, cleaning them with electric safe contact cleaner, allowing them to thoroughly dry, and reseating them. The grease would be better suited around the edges of the harness connections to keep contaminants and importantly moisture out to prevent corrosion / bad contact.

 

https://www.tacomaworld.com/members/andy01dblcabtacoma.359086/
Correct.
PIN number 4 and 13 could be jumped to read the ABS codes by reading the flashes.
Could you post what the codes readings mean ?
I have them, but others may be able to make use of the codes.
I know that they tell you if you have a speed sensor that is bad and which wheel is defective/faulty or if there’s another issue. Later this evening I will try to upload an image of the code chart that goes along with the flashes it displays when jumping the OBD port

 

These are screen shots from the FSM. The FSM is pretty easy to obtain... I usually don't post whole pages cause I rather people get the FSM and learn how to use it (teach a man to fish and all).




And yes, the ABS codes have a similar procedure and code chart.

 

Recieved a TOPDON ArtiLink600-OBDII- ABS/SRS scanner today from Amazon which has a 3 RESET SERVICE and was able to clear my SRS/AIRBAG light that was on constant.
Have not yet to drive my Taco, but am going to do so shortly and hopefully the light will continue to stay off.
Will follow up with an update once driven a few day's.
Seem's like this scanner worked better than expected, rated great reviews on this model. Will keep everyone updated on the outcome.
Wanted to thank everyone who chimed in on this post. Did not remove anything nor apply and dielectric grease to any connection. Saved me time on ridding the light, but time will tell.
Thanks again for the help/suggestions.
On the road again
For the price of the TOPDON 600, I wold recommend getting one of these. Cost me a total of $85.59 and according to the manufacture, they give lifetime updates.
Cheers !!

 

Well, been driving my taco for a few weeks now here is what is happening after clearing all the DTC codes stored by using the reader/scanner.

this is what the DTC codes read.
The light has been back on since the initial reset and each time I have to reset it, sometimes it comes back on immediately and others, days.
Still have yet to remove the module and clean the connections and thinking since the SRS is currently not experiencing any issues, the system is fine but may be losing connection/communications to the module from every day vibrations?
Thinking of removing the negative battery terminal, all the connections to the module applying electronic parts cleaner with a very soft toothbrush and a dab of dielectric grease on each connection terminal may resolve my issue.

 

Bumping this old post because this exact problem popped up today when I started my truck.

Not sure I'm technical enough to understand all this but will go do the checks & try to locate that module.

Only thing I do know is that I've heard of a clock spring before & that's nothing I'm gonna tear into.

 

Ok so where is the air bag module & the SRS module?

Are they one & the same or different things/locales?

 

Did some more searching & found the thread on the location. Yay! Now to see if my scanner will tell me anything.

 

My scanner didn't tell me anything or even show it as a code.

What's next step? Take the module out?

 

Most scanners won't show SRS or ABS codes. They are not ODBII spec'd.

The FSM has a procedure to get the codes:


I highly encourage you to get a copy of the FSM (there is a sticky thread at the top of the 1st gen forum) and read through all of the pages in the "Diagnostics##Supplemental Restraint System##" section.

 

Thanks!

So still being "scared" of something going off & hitting my wife in the face.
Took it to my local guy who said he had a snap on scanner that could read anything.
10 mins later & $40 for his time= my issue is the clock spring according to his reader.
No biggie, I'm capable of changing that & he gave me all the info to do it myself cause he said for sure he was gonna be too expensive to do it.

Got one on the way & watched several videos already to be safe.

Thanks to all for holding my hand. This little Taco is just about at the end of its lifespan & things are starting to have issues. Been a great ride & for a little bit we'll keep patching her up.