4L60E略亮2-3次班次？可能是一台坏电脑

In the past, hints and suggestions for causes of 4L60-E 2-3 flare have invariably been centered on problems inside the transmission. Some of the most common causes are low line pressure and internal leaks of 3rd gear oil. More recently,

信息已经提出了输入壳体，其中3-4个活塞进给孔中唇部密封区域中的3-4活塞饲料孔。在4L60-e上，现在可以添加到可能原因的可能原因列表列表的另一个竞争者是一个坏电脑。

This month’s problem vehicle is a 1998 GM truck with a flare on the 2-3 shift before and after overhaul, with no trouble codes. The shop installed a second valve body with all solenoids but it didn’t help. Line pressure was normal in all ranges as well as when the flare occurred. When a new computer was tried, the problem went away. The puzzling thing was that line pressure was the same with both computers, so what was causing the flare? One clue was the “B” solenoid data on the scanner would sometimes flash “short” when the problem occurred. This is when the amp meter came out to assist in diagnosis.

大多数现代DVOM可以选择检查当前（AMPS）。如果您从未完成过灵流绘制测试，我会鼓励您通过检查DVOM手册，阅读过去的技术提示（2002年11月的传输摘要）或关于较新型迷你钳位的最近技术文章。检查安培数既不复杂也不困难，并且通常比欧姆测试更容易或其他更常见的电路检查。在运行中测试电路是确认良好电路的最有效方法之一。一旦您对该概念感到满意，它成为一个强大的诊断工具。

For this vehicle I tapped into the传播通过用DVOM的两个引线取代“Trans”保险丝来+正电源。现在，该电路的所有电源都流过DVOM的放大器部分，电路仍然受到仪表内部保险丝的保护。图1shows the set-up using a conventional DVOM. With the key on and using a scanner with bi-directional controls, the next step is to command 3rd gear, which turns both “A” and “B” shift solenoids off on a 4L60-E. At this point, zero-out the DVOM so the current draw from any other components sharing this circuit is canceled out and you are monitoring only current changes you command from this point on. Commanding 4th turns only the “A” solenoid on, while commanding 2nd turns only “B” solenoid on.

使用此简单的DVOM设置，我们观看了当前的绘图变化，因为每个电磁阀打开和关闭。虽然两个电路的最大电流抽取几乎相同，但它们的行为不是。关闭时，“A”螺线管在一秒钟的一小部分中会降至零，而“B”螺线管将需要大约2秒钟才能降至零。我们使用Snap-On™Vantage的图形能力录制了该行为，以便仔细看看，并向您展示我们在DVOM上发现的图片。图2.显示了比较“A”和“B”螺线管时的差异。当计算机没有干净地关闭“B”电磁阀，它不会足够快地排出其油，而2-3换档阀将逐渐移动而不是从一个位置移动到另一个位置。这允许2-4频段暂时瞬间在3-4离合器施加之前熄灭，导致2-3张火炬。

导致计算机内部的此问题是什么？没有物理触点，即在继电器中打开或靠近。所有电磁控制器或输出驱动器都是固态电路。它可能是从腐烂电容到硅芯片的任何东西都糟糕，因为有人在洁净室被打开时。我在本地看到了两个问题的车辆，所以有很好的机会，那里有更多的糟糕的电脑。因此，如果您跨越2-3张火炬，请记住计算机作为可能的原因。

感谢杰夫戴维斯在Rockenbach Chevrolet和ATSG的JON Glatsein对本文的贡献。