Fluke 179 off readings (VDC, ohms)

[hunter_sk]

I have an issue with Fluke 179 precision. Ohms range shows about 30M when should be OL, and around 30 ohms when closed and decreasing to ~1 ohm for about a minute. (probes are fine)
VDC shows about 250mV on open loop when should be 0. Internal resistance is about 11M (sounds fine to me) and sending 1mA to probes when measuring resistance.
VDC on 9V battery shows difference from other DM about 0.2V.

I've measured reference voltage on pins 10,11 on IC and it's 2.5V. MOVs shows high resistivity (OL on my Voltcraft MT-52). Also measured some testpoints to discover abnormality. Most of them was 0.8V, one 4V sharp, TDI/TCLK shows about 0.05V  , P2.1/TB0 was negative

I'm not an electrician, just enthusiast, so just investigating from every sources I can get.
If someone can lead me to what I can check or when I can find that leak, I would be grateful.

[retiredcaps]

Suggestions.

1. Clean entire PCB with IPA and let it dry thouroughly.  If you have debris, dirt or previous alkaline battery leakage, this will affect your readings.

2. Check your PTC.  It should be around 1Kohm.

3. Check your range switch for dirt, debris.  See

http://mrmodemhead.com/blog/fluke-83-iii-rotary-switch/

4. Check for dirt, debris, soldering around the input jacks.

[hunter_sk]

Thank you for the suggestions, retiredcaps.

1. Cleaned 1 year ago (part was corroded), then it was dead brick. I have repaired missing traces and still dead. After 1 year I have returned to it and it runs, but some values are off, some floating (decreasing ohms)

2. PTC 1,11k

3. Rotary switch looks OK to me, clean

4. Jacks looks OK

It is OK to flood some true hole connections with solder? I have an bad feeling that that ones, which have been corroded may have loose connections inside in middle layers of PCB.

Measured values:
VDC open 0.035V, closed 0.03V
mVDC open -60mV, closed -1.9mV
ohms open 12-20M
ohms closed 12 and decreasing to 1 for 1-2 minutes
9v bat with Fluke 179: 9.34V
9v bat with other dmm: 9.5V

Thanks again for help

[retiredcaps]

If something was corroded, I suggest an IPA bath first of the entire PCB.

In the past, I bought used and abused Flukes.  One was particularly dirty and when I shorted the probes, I would get -2 ohms.  It took 3 repeated IPA cleanings of the entire PCB before it properly reads 0.2 ohms.

Your PTC measures good.