Philips 37PFL5405 - Q552.1LE - shorted HDMI switcher SII9187

This Philips did not start up and blinked twice. I activated the SDM via the test point on the main board and it gave me error 15:

I know from previous Philips repairs that very likely some voltage required for booting is missing.

This TV is no beauty. The chassis is unnecessarily bulky plastic. The sole reason must have been to make the cheaper series also look cheaper.

So I started main board debugging, which is quite fun with Philips devices due to their excellent service manuals.

I found the voltage regulator 7U03 on the downside, which was supposed to output 3.3V, but all it had was 1.1V. It also was getting quite hot.

Next check: is the regulator broken or the output line shorted? I measured some 500 Ohms on the line. This did not look like a short to me. To be sure, I first lifted the regulator's IN pin off the board and attached my multimeter to measure the current. A whopping 1.2A was flowing, which is way over the spec of the regulator. It was in protection mode and limiting its output current. It had to be a semiconductor, whose short only appears when voltage is present.

So I also lifted the GND pin and soldered a wire to the OUT pin to attach my power supply. Aha, the supply did the same and limited the current.

1 ampere is enough to turn the responsible current sink on the board hot. I moved around with a finger and identified the HDMI chip SII9187 as the culprit. Uh oh. A large quad pack chip in a very inaccessible position.

I managed to remove it without too much collateral damage to the plastic socket holder. Those audio sockets are practically impossible to remove and I figured that it's not needed if I pointed the hot air gun away from them.

With the chip removed, the 3.3V came back and TV booted up fine. That seemed to be its only problem and I was confident to get it fixed with a new chip.

The chip is available only from Asia. I ordered a bunch via AliExpress (3$ a piece). To make the most of the shipping costs I also threw in 5 pieces of its sibling, the 9287 (1$ a piece), because that one is also very common in Philips devices.

Soldering the big quad pack chip tested my patience. I succeeded on second try with the first chip.

Hallo Frau Johansson!

This is not a pretty TV from the outside, but the image is decent. The very thin and squeaky sound is not so exciting, though.

A cheap repair for 3$.