Highline Stereo Faults

Highline Faults

The 1st reported fault that I heard about was in late 2014. Since then, the faults have been rolling in. Strangely, it’s now not just 1 fault but several which shows that the Bosch unit is very unreliable.

The faults covered here are:

Unit Freezing
Screen Lighting Failure
Touchscreen Failure
Turning off and on

Unit Freezing

In early 2015, the 1st story appeared of the Bosch Highline stereo failing. The stereo froze more and more often until eventually it didn’t work at all. Normally, the stereo would be fine until it warmed up, then it would start to glitch and freeze. The time it took from initial problem to total death differed between owners.

Having looked at a few of these failures, I have made my diagnosis.

Corrupted RAM

Each of the tested units had corrupted sections of RAM where Windows CE was loaded. So, unfortunately it looks like cheap memory was used and they are beginning to fail.

When this happens, the unit will generally freeze on the start up screen or asking for an update. However, installing an update will fail, usually claiming there isn’t enough storage.

Solder Joints

The fault also looks like a fault with a cracked solder joint but so far, I haven’t found any.

Overheating Transistor

There 2 main culprits, the power transistor and the amplifier. The amplifier transistors are heatsinked to the back plane of the stereo.

Under the rear plate, you can see the 2 bolts that hold it in place.

With the back plane off, you can see the transistor set. If this over heats, the stereo blacks out. Try cleaning it up, apply new thermal compound and retigthen it to the back plane.

The power transistor is further inside the stereo (left).

Better cooling may or may not fix the problem as they may be getting hot because of an internal fault.

Fixes?

Nope. I scanned the memory for bad sectors and made a note of the positions. Running the stereo until it died and scanning the memory again showed that the corruption had increased until it had affected an area holding an important file or driver.

There is no way to reinstall WinCE into memory in a way to work around the corruption. Even if you did, the corruption would just spread and find the other sectors eventually. Apart from desoldering the RAM chip and soldering in a new (better) one, there’s nothing you can do apart from throw the unit away and buy something better.

Cleaning the transistor face, applying new thermal compound and retightening it may help. This fixed one of the stereos I looked at. The other 2 with the same problem still crashed.

The Highline is a shit stereo even when it does work properly. Take it as a sign to upgrade it.

Screen Lighting Failure

This was the 1st common fault reported on the unit and I believe it’s why they upgraded the internals of the unit to a different version. The LED screen lighting fails or dims so much that almost no light can be seen at all.

I haven’t been sent one of these failures to investigate yet so I don’t know for sure but either the LED diver failed, the solder joints have cracked or there has been a failure of the LEDs.

If you have one of these Highline units with a failed screen light and have swapped it for a better stereo, please let me know as I’d pay the postage to take it off your hands. Until I take one apart, there is no way I can see what the fault actually is.

Touchscreen Failure

More often than not, the entire touchscreen digitiser layer fails to function but there have been rare cases of sections of the screen failing to respond to touches. This makes me thing that there is a fault with a connection to the digitiser layer or a break in the ribbon cable. It looks to be a 063020 touchscreen available on AliExpress but I haven’t tested one myself.

Screen Artefacts

Parts of the screen not working, coloured lines down or across the screen, big blocks of colour. If this is your only fault, it’s worth taking the unit apart to disconnect and reconnect the screen ribbon cable. It may just be a bad connection to the PCB but it might also be a fault inside the screen.

Turning Off And On

Possibly some component over heating, causing it to shut down.

Rebeka found that pressing the “screen open” button stopped the on/off cycle on her unit.

Conclusion

The Bosch Highline stereo is a piece of shit even when it works properly. It’s over priced, no TMC in many countries, low resolution screen, slow, UX is terrible, GUI is outdated
and the satellite navigation is terrible as the maps are from 2014 and you can’t do a full postcode search. The fact that these units are also incredibly unreliable is an insult. It’s unbelievable how much people sell these units for on eBay. The 2nd hand unit’s value may be £400 but they are worth less than £100.

If you have a Highline that has failed, don’t mug yourself off and replace it with another one. Buy something better that won’t fail again in 2 years.

Replacement Options

I’m not going to put actual model number here as I’ll be forever updating it. However, take a look at the Panasonic AVIC stereos and see what suits you.

If you have an Apple iPhone, do a search for Apple CarPlay stereos. If you have an Android phone, do a search for Android Auto stereos. Pioneer, Alpine, Kenwood, JBL and JVC do very good stereos that have the Apple and Android options.