One of our customers rebuilt an AW55-50and had repeat complaints of a 2-3 shift flare. Everything on thetransmission这个投诉是纠正和复查. Everything on the valve body and control side of the complaint was done, checked, verified and looked at once again. Resets/relearns, you name it, they tried it. Eventually another valve body was tried, but the car continued to have the 2-3 flare. With everything appearing to function perfectly, or at least being capable of it, the vehicle was sent to a dealer to have them try the computer reset. It didn't work - once again, the problem refused to go away.
您熟悉2002沃尔沃XC90模型的人知道他们在CAN系统上运行（控制器区域网络）。如果您尚未熟悉罐头，请将其视为共享的沟通行。CAN系统是用于沟通和控制在整个车辆中以电子方式运行的所有内容的网络的网络。在仔细审查这辆车寻找2-3耀斑的原因，我们的客户确实发现了车辆的后刹车灯：两个灯泡被烧坏了。他取代了灯泡，但制动灯仍然不起作用。经过一些接线图研究，他意识到制动灯由模块控制，该模块在网络上。
Could it be as simple as something wrong in one computer preventing the reset of another computer operating on the same CAN? The only way to verify that was to find and repair the brake system problem. While tracking the wiring for the brake lights, our customer found a little black box that did not appear in the wiring diagram. It was an aftermarket trailer light adapter. Although they are not at all uncommon, the aftermarket brake box was totally unacceptable as far as the factory control module was concerned.
After installing a "factory" trailer box on the Volvo, the dealer was able to correct the brake circuit fault in the control module and then successfully reset the transmission computer. Two-three shift flare gone: problem fixed.
The lesson here is not to be on the lookout for aftermarket electronics. The lesson is to remember that old rule about checking and clearing all codes and all systems. This has been a rule to follow for a long time on vehicles using multiple modules which share information such as an engine controller and a transmission controller. It is even more important to remember this rule with a CAN system. Faults in one system may prevent a relearn in another, and there will be nothing to tell you the reset was not applied!
Serge Martin is Technical Director of Matech BTA Inc., Quebec, and a member of the SonnaxTASC Force®(Technical Automotive Specialties Committee), a group of recognized industry technical specialists, transmission rebuilders and Sonnax Industries Inc. technicians.
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