1998 v70 Service Light Reset 'Tool' ?

[MrAl]

Hello again,

Yes if i had a DB9 connector to ELM to car i could send signals to the DB9 via micro controller, the same way i do it for communications with the PC RS232 port.

I saw one cable for DB9 with ELM in it and it was 99 dollars !
I'll have to look some more i guess.
What is strange is that some of them just say "DB9 to ODB2" cable, but they dont specify that is has ELM built in too. I cant take it for granted that it has it because it may not.

So i guess all i really need is a low cost (or fairly low cost) DB9 to RS232 but with the ELM327 chip built in too. Think that should be doable for under say 30 bucks?

[esl_97_850_T5]

...I saw one cable for DB9 with ELM in it and it was 99 dollars !
I'll have to look some more i guess.
What is strange is that some of them just say "DB9 to ODB2" cable, but they dont specify that is has ELM built in too. I cant take it for granted that it has it because it may not.

So i guess all i really need is a low cost (or fairly low cost) DB9 to RS232 but with the ELM327 chip built in too. Think that should be doable for under say 30 bucks?

MrAl,

1. I see what you mean. My suggestion to search Amazon and eBay for "ELM327 OBD2 DB9 RS232" yielded cables which did *not* have imbedded ELM327.

My apologies!!

With further detective work I couldn't find any affordable (<$30) ELM327 cables which have a DB9 connector. I guess most everyone has instead transitioned to the ~$10 ELM327 USB cables or ~$10 ELM327 Bluetooth (or ~$?? ELM327 wifi for those that have Apple products).

2. If your microcontroller can't interface directory to a USB port instead of a DB9 RS232 port, then you might try to glean some ideas from this hack of the ELM327 board from an ELM327 USB cable in which the hack bypasses the USB interface and allowed this guy's Arduino to interface directly to the Rx / Tx lines:

http://www.instructables.com/id/Hack-an ... BD2-Scann/

I have no idea if that would blow anything. Experimenter beware.

With this hack approach, you might be able to get buy with the ~$10 cost of the ELM327 USB cable (instead of the up to $30 that you mentioned), plus the cost of your microcontroller with associated interface circuitry, plus the inconvenience of hacking the ELM327 USB cable.

3. Is using an out-of-the-box Arduino w/ an imbedded female USB plug along with an original, un-hacked $10 ELM327 USB too costly? If so, that seems like a cleaner approach.

4. This might also give you some ideas since it is open source:

http://en.wikipedia.org/wiki/OBDuino

OBDuino is an open source trip computer design based on the Arduino platform. It is overkill with respect to resetting the SERVICE light. But it could be programmed (since it is open source) to do most any of the KWPD3B0 programming that is available via the open source volvo850diag's .js and/or .html file.

5. Good luck.

esl_97_850_T5

[MrAl]

Hello again,

Hey thanks for the info again.

Something like these should be doable. I found a data sheet on the ELM327 chips and i see that they are just basically an OBD2 to RS232 translator. That means pins on the chip for OBD2 and pins for RS232. The device manufacturers must be using a separate uC chip to go from RS232 to USB probably because that's the main consumer solution. So all i'd have to do is find the two pins for RS232 and cut them away from any other traces and then use the pins directly with a separate uC chip. It's much easier to go from uC to RS232 than from uC to USB, and since the ELM chip is innately RS232 it seems logical to go with RS232 instead of USB.
Strange though, the devices being sold are around 10 dollars each, while ELM seems to be selling the chips themselves for 20 dollars and up each. So it would be cheaper to buy a whole unit and then hack it
The chips look pretty easy to use too.

Yeah i see that one link they are using the Arduino. That might be so they can use the terminal software sketch or something to communicate with the ELM chip. That's probably a fast turnaround approach. I happen to have an Arduino Uno too

Have to give this some more thought i guess.

Thanks again for helping me get started in the right direction.

[esl_97_850_T5]

1. You've grasped what I was trying to convey.

You're welcome for the directional guidance.

Look forward to seeing whatever solution you come up with your SERVICE light resetter.

2. There's a fair number of people that want a handheld device that can do the equivalent for '96-'98 850/S70/V70/XC70 of what Vol-FCR, Brick-Diag Free v0.0.6.6, and volvo850diag / kwpd3b0_interpreter can do, preferably with OBDII emission diagnostic capabilities like Torque Pro has, with live data displays, etc.

But that's a more complex tool. I guess you can take "one bite out of the elephant" by coming up with a microcontroller-based SERVICE light reset tool which is much cheaper than a DRAPER.

Then maybe you or someone else might be so inclined to build upon whatever you come up with.

3. As far as why the entire ELM327 clone USB cables can be ~$10 (even including a RS232-FTDI converter chip), when the cheapest official Elm Electronics ELM327 chip is ~$21, chalk it up to low cost Chinese manufacturing of an ELM327 clone which is largely equivalent to an official ELM327 v1.4, has not paid Elm Electronics for any licensing rights, doesn't have some of the Elm Electronics OEM specialization capabilities (involving AT@1 and AT@2), low cost of the RS232-FTDI chips, and low cost of Chinese manufacturing for the entire cable.

esl_97_850_T5

[MrAl]

Hello again,

Do they even sell that "DRAPER SERVICE LIGHT TOOL" anymore?

[songzunhuang]

So, what happened to this thread? Was a device ever created? I see it’s 5 years old, so maybe someone just lost interest.

[songzunhuang]

I just ordered an OTC 3596E Oil Change Service Light reset took from a seller on eBay. He indicated that the 1998 V70 is listed in the manual. This one was a pretty good deal at $75. Yea, still a lot to just reset an indicator light, but I don’t want to pull the bulb.

In any case, when it arrives I post a full report of how everything went.

[slickdizzy]

If you have access to an Android device with Bluetooth, there is a sub-$5 app called “850 OBD-II” that can reset the service light among many other useful functions (read Volvo-specific DTCs, run system tests, etc) on 1995-1998 P80 cars. It reset the service light on my 1998 V70 with no issues and has also been extremely useful as I try and get the car through an OBD2 emissions test.

I purchased a Bluetooth OBD2 dongle from Amazon and now have near VST-level functionality for less than $50. I would HIGHLY recommend that any 1995-1998 P80 owner invest in this setup.

App: https://play.google.com/store/apps/deta ... i&hl=en_US

Dongle I'm using: https://www.amazon.com/Veepeak-Bluetoot ... 076XVQMVS/

[songzunhuang]

Oh snap! I have ODBII dongle that works on wifi. The application I use with it on my iPhone called "DashCmd", didn't work with the reset light. I wish I had seen your post earlier! Although, since I don't have an android phone or the $50 dongle, maybe I still came out ahead. We shall see.

[songzunhuang]

MVS folks, I am happy to report that the tool I got from eBay arrived today and I was able to reset my "Service Engine" light in about 1 minute. Everything was as easy as I expected. Just attach the adapter for the ODBII in the center console. Insert key and turn to 2nd position. Use the on-screen instructions. Pick a few items and "BAM!" You are done.

Here's my experience in pictures.

Contents of the kit.

Just pick a few menu items.

TheSteps.png (868.47 KiB) Viewed 907 times

All done!

TheResult.png (713.58 KiB) Viewed 907 times

So, go find one of these on eBay. They are plentiful and it worked well for me! I am not sure how it could be any easier.
The cost for me was about $75 including the shipping.