Fluke 85V is not your cheap industrial multitester and the price of this multitester soars high. Of course it is FLUKE! That even a highly sophisticated brand is still susceptible to failure. This unit was shipped for repair and the unit is totally dead, even with a new battery installed. The tester does not turn on.
At first it was handed over to other troubleshooter here in my country but to no avail. So they sent it to me. The owner did not hesitated.
Upon opening the unit. I smelled something inside. The board was sprayed with WD40. What the F? board is flooded with that lubricant. What in the world does the first repairman was thinking? Damn!!!
So before getting deeper with the repair. I immediately clean it with the right cleaner to remove the residue of the WD40 on the mainboard. 99% iso alcohol is the best cleaner there is and not 70% alcohol.
Troubleshooting can be a pain in the brain without any schematic right? Fortunately world wide web offers free download. It helps me even better.
Printed it and enlarge them so that I can easily trace the problem. TEST POINTS comes in handy too. Values are all correct on the test point areas.
Fault tracing begins and upon testing all components. Found 1 transistor shorted. Getting further pointed me to a component near the MCU or microprocessor. Since all voltages are of correct values according to the schematic. It just mean the MCU isn't actually working on the right frequency and does the MCU oscillator might be at fault. An Oscilloscope might detect ot easily but I do not have any so I replaced it and VOILA!!! The unit comes alive in no time. Test again all the voltages and still exacly the same.
And Then the unit was repaired.
One noticable thing on this tester LCD was it already have the so called LCD sunburn issue.
But for the meantine I'll just leave it that way and when its time to replace the polarizing film, Then will do the job later just like the other FLUKE multitester that was posted earlier on this site that has LCD issue.
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