I recently purchased the Launch OBD II scanner from Harborfreight for $40. When I plug it into my '97 850 (check engine light is ON), instead of displaying an error code, the unit just gives 4 dashes (----). The unit does reset the check engine light as advertised though, but then it comes back on after a while - not surprisingly since I have not fixed the problem. I went through this several times now. So I finally went to Auto Zone to have the error code checked (for free). Their reader saw code P0410 (Secondary Air Injection System Malfunction). That's exactly what my mechanic' reader had found (after he replaced the relay on the auxiliary air pump, the light came back on after a few days...).
Bottom line, my code reader does not see the P0410 code.

My question is: Has anyone else had trouble with that cheap little Launch OBDII reader from Harborfreight? I wonder if I was just unlucky to get a bad unit, or if it is general problem with the product. So far I have only seen good reviews of it.

Thanks.

These scanners are ok, but to get more details on the P0410, I don't know of any place but the dealer where their scanners will give the '1-2-3' Volvo codes. With the P0410, you are likely looking at the Air Pump and/or the Check Valve or possibly the relay that turns on the pump. The dealer can actually turn on the pump with his reader to see if it is the relay or pump. Aither way, do the Check Valve when you do the job.
Where in CT are you? I live in the Waterbury area.
Good luck - Marty

At first, my mechanic replaced the pump. Couple weeks later, CE light came back on, he confirmed pump itself was functional, and replaced relay. CE light came back on after 2 days. That's when I decided that I could do just as good a job myself. The light comes on rather sporadically (after I clear it), sometimes it takes days, sometimes even weeks for it to reappear. Seems to be more frequent in cold weather. Don't quite understand why that would be - does it suggest the system is "kinda" working, just not really well? Anyhow, assuming relay and pump are functional, I'll focus on the Valve and any vacuum leaks. Whatever I fix, I'll then have to drive around for days or weeks to see if that light comes back on. Not my idea of instant gratification...
Meanwhile, Harborfreight has agreed to exchange the unit - hopefully the replacement will work better.
I live in Branford - same neck of the woods!

Some codes that turn on the Check Engine light are proprietary Volvo codes and will not show up on a generic OBDII scanner. Most scanners will be able to erase the codes, though. I have a generic code reader I bought at AutoZone for $180 (ouch!) and it does not see all the codes, but extinguishes the CE lamp even when it can't display the code.

This whole OBDII thing is a racket to help dealers raise the revenue in their service departments. It always ends up being a trial-and-error game in the end and OBDII is mostly useless in helping to diagnose. I had a Check Engine light problem that would not go away until my dealer kept the car for almost 3 months (under warranty and I had a free loaner) and replaced everything in the fuel evaporative system possible including the gas tank. Ended up being some small gromet that was apparanly missing from the factory (the car did this since 1500 miles). So much for the OBDII as a diagnostic tool.


Good luck.


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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 - hers,

Actually, in my case the error code displayed by the other scanners (P0410) is generic. This code is listed in the manual that came with my scanner. So in this case it is not a proprietary code, and the scanner should detect it, IMO.

Anyway, here's another fun OBD II related story. I live in Connecticut. They recently started a revamped state emissions control testing system. Turns out, for cars new enough to be equipped with OBD, all they do is plug in a scanner to see if there are any error codes. No actual emissions are tested !! I am sure there are many potential problems that would increase emissions, but not be picked up by OBDII.

I see your point. Your unit is probably defective.

As far as the "revamped" emissions testing, it's been the way you describe for several years now in Massachusetts. They just plug the cars that are '96 or newer in and take a reading. Actually, I think this is valid, since by law, '96 and newer cars are required to turn on check engine and store codes when there is even a slight emission problem. Moreover, if you had a CE episode and reset the light, chances are the car will not pass the plug-in test because there is some magic bit that needs to be reset in there that gets set after some sonditions have been met. So, just resetting the CE light witha gadget from AutoZone may or may not make the vehicle pass emissions. Of course, they are reading the memory of a computer and we all know that nowa days any 13-year old kid can hack computers... Just look at the computer virus outbreaks lately. This system can be fooled for sure. Whearas if you actually accelerate the car to 60 MPH and sniff its exhaust, it's pretty much undeniable.

But until the ECU hacking becomes rampant and cheating the emissions tests is commonplace, I don't think the authorities will pull their heads from under the sand.

And, oh, by the way, all those junk heaps that billow black/blue smoke as they drive down the street? Well, they are exempt from emissions testing for old age. PLEASE!

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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 - hers,

Don't you love them bureaucrats!

On Harbor Freight scanners, a lot of guys swear by them. I don't have one mainly because everything else I've bought from HF ended up as a door stop and their "free" shipping is free until you get the invoice and see the $5.00 "handling fee" tacked on that they never mention (at least that I can find). They also ship parcal post which from CA to VA takes about a month or so. I'm just not a big fan of them

bl

Software to read Volvo codes is available here:

http://www.onboarddiagnostics.co.uk/volfcr/index.htm