Black Top Problems

[tjmr2]

FWIW: According to this forum the Black Top ECU can suffer from a transistor meltdown from excessive cycles without the transistor being able to dissipate the heat. While their English language skills may not be the best their logic makes sense to me.

Typical Problems of Toyota Corolla Levin / Trueno AE111 20v MAP ECU (aka blacktop)

The bottom line is, if your BT doesn't seem to be making the kind of power you think it should (doesn't seem like the VVT kicks in) open your ECU up and look at the transistor pictured. If it's blown replace it or have it replaced and put a heat sink on it.

Since a transistor is a proportional switch (very simplified) if switched too fast - too often it can easily build up too much heat leading to burning up the transistor.

This might or might not be a problem, but thought it worth pointing out. Has anyone on this forum seen this problem?

I'll be checking my ECU in the next few days to look for the transistor in the photos.

[mr220v]

This article comes up every few months. I've owned a few BT ecu's, and have never seen this problem. If it did come up, the fix is easy.

Part of the reasoning in the article is that the silvertop's vvt comes on at 4500rpms and the blacktop's comes on based on throttle position, and therefore more frequently causing the failure. The problem is that no silvertop ecu activates vvt at 4500rpms. All 20v ecu's activate vvt based on throttle position, so would be equally likely to fail.

On a side note, you harness goes out tomorrow.

[tjmr2]

I'm glad it's not common, and you are right the fix wouldn't be difficult. I just wanted to see if our community had seen this problem.

Thanks for the update on the harness.

[mydejavooo]

Originally Posted by mr220v

This article comes up every few months. I've owned a few BT ecu's, and have never seen this problem. If it did come up, the fix is easy.

Part of the reasoning in the article is that the silvertop's vvt comes on at 4500rpms and the blacktop's comes on based on throttle position, and therefore more frequently causing the failure. The problem is that no silvertop ecu activates vvt at 4500rpms. All 20v ecu's activate vvt based on throttle position, so would be equally likely to fail.

On a side note, you harness goes out tomorrow.

Just out of curiosity...is the 20v swap an "easy" swap? Also, how much are the legendary mr220v harnesses I hear so much about?

[mr220v]

It's an easy swap if you get my harness. $350+$30 return shipping. I can work with cut 20v harnesses, which will save money.

[F0Bman]

Great, thanks for the tip.