Blink code question

[Jwct]

Hi, I am having a bit of trouble with what I think is basic understanding of the blink code process and hoping someone can help me with a couple questions.

The check engine light came on the other day with no notable symptoms while driving (1993 500E). I checked the 8 pin connector by the battery and got a code of 10 out.

Following gsxrs pinned post on diagnostics, I believe that corresponds to pin 19 codes (diagnostic) on the 38 pin connector which is high voltage at the MAF. I reset that code and the CEL is off but when I test I still get code 10 from the 8 pin connector,

Just want to be sure I am following the process correctly. The car was just in the shop for a transmission replacement and while there I had a new battery installed, I am thinking if I have the code right it’s probably related to battery swap or the shop trying to charge/jump the old one.

Just want to be sure that I am in the right neighborhood and the codes not something related to the transmission.
Thanks for any help you might offer, I’m new at this!

Thanks!

 

[nocfn]

See if you turn the car on, let it adapt…. Not ignition but all the way so all lights and buzezers are going. About 15-30 seconds you will hear audi le change as the eta resets adaptation. Then Get it to temp and drive it. After 20 spirited miles at temp, include kickdown from 56-85 etc, see what codes you get.

 

[gsxr]

Jwct, you are correct, code 10 at the 8 pin connector by the battery corresponds with pin 19 at the 38-pin diagnostic port... both of these will show you blink codes from the Diagnostic Module, which is what drives the CEL.

Code 10 is indeed for abnormal voltage from the MAF. It is very unlikely either the transmission swap or battery replacement is related. Ideally, the next step would be using a hand-held blink code reader to check fault codes on the LH module (pin 4 at the 38-pin diagnostic port).

Note that after clearing / resetting a code from the DM, it requires an engine start to fully clear. It may also take a couple of engine starts before the CEL will turn on again, if the same fault is still present.

Is your upper engine wire harness the new style with good insulation? The MAF connects to the upper harness, if original, that should be replaced pronto. Most cars have already had this harness replaced by now.

 

[Jwct]

Thanks to both @gsxr and @nocfn for the replies, I have started a few times and driven it around town and so far the light remains off. The harnesses have been replaced, I’ll give it a few days and see if the light remains off. I do have a hand held code reader that will be my next step,
In any case it’s a(nother) good reason to drive the car frequently!

 

[Unavita]

I too used the blinker and have a solid light indicating #14 which is Lamda On/Off ratio. Everything I have read so far indicate an ECU problem- maybe a EHA??