Datron 1281 error 2893 repair

[syau]

My Datron 1281 developed an error 2893 which points to the Ohms assembly after I return from vacation Switching in pathway 056 and found the system giving a value of 0.010078. I tried to do a internal source cal but it end up to the same error 2863. I have swapped the M201 and M202 (DG211CJ) with the same result

Could anybody please share the the value of pathway 056.

[doktor pyta]

On my D1281, P056 gives +0.010025V (last digit unstable).
Don't give up

[syau]

Dear doktor pyta, thanks for the info.

Did some measurements on the resistor R209 and R210 found within limit. Cleaned the board with IPA yield the same result. Will do a external cal later as suggest by another member.

[pelule]

I am sorry to post that late, but I was offline due to a surgery some time.
I just read your post.
This error occurs when the internal sources have drifted over time.
You just need to due a "internal source calibration" to solve that problem.
+ Enable calibration (key)
+ go to cal menue
+ select ext cal
+ quit (do not execute)
+ next you will be asked if you want to do the internal source calibration - trigger it
But the 1281 must be powered on at least 48hrs to ensure thermal stabilisation.
Thats the way to continue operating over long periods without calibration.
/PeLuLe

[syau]

Thanks pelule for the tips  and the self test now passed.