At 05:00 16/04/02, you wrote: >I have identified all but 2 of the >Chips, and if any one can tell me what the MG2520 10M23B and the MH614 10M20 >are, I'll look to replace / reprogram them.
Are you able to look through archives for this mailing list? I posted the following in September last year: "I just removed the ECU from my bike. The Yamaha part label on the casing says 4BH-8591A-00 (UK-spec). The small Toshiba logic chips (IC602, 306, 304, 305, 603) and the larger Hitachi chips (IC302, 303) are the same as the illustrations on www.gts1000.org. Incidentally the number suffixed H on the Toshiba chips is almost certainly a date code: 9237 would be 37th week of 1992. One Hitachi chip is a programmable timer HD63B40P CMOS PTM (programmable timer module) with 2.0 MHz clock frequency. The other is a HD63B21P 2MHz CMOS peripheral interface adapter (PIA). If anyone has a subscription to chipdocs.com or similar, they could get more information about these devices. [] The code on the ND chips is different on my bike to the website photos; IC301 is marked MG1730/9M14 and IC701 is marked MH614/8M20 [] one of the ND devices is a One-Time Programmable MCU, and perhaps the different codes mean different programs for the various specs (UK, US, '93, '94) ?? I know nothing about IC781 (the upright device in a cage, picture 8; it has a "window" like an EPROM, but it also unquestionably has an air-hole, which favours the explanation than it is an atmospheric pressure sensor. [] there doesn't seem to be any feasible way to re-program" I think that still stands - re-programming is out as a practical solution, and not required anyway. Your symptons are those of sensor or wiring loom problems, perhaps an ECU fault, NOT those of a badly-programmed ECU. You may not have the same spec ECU as mine but I doubt if there are significant changes, certainly not as to cause the problems you describe. >Motec ECU should fix this. This (or fitting carbs) would be very low on my list of possible remedial actions. Fact is that the GTS injection works fine if in good condition. I'd try the following in this order: 1) Borrow another known good ECU for testing by substitution 2) Check, either by substitution or by tests given in workshop manual, the functioning of *all* the devices providing input to the ECU, e.g. TPS, APS, r.p.m. sensor, temperature sensors, etc. 3) Check your wiring loom and the plugs to the ECU for shorts, bad contacts, etc. >Oh and she made 88.6 EEC BHP at the back wheel in 4th, topping out at 146 >MPH, for those interested. Which, allowing for transmission losses, is about right - although you don't mean that it was doing 146mph in 4th gear, do you?! HTH, David Thurgate http://www.uranus.co.uk/M_cycles.htm =================================================== Kawasaki ZX750-A1 in Tony Foale FFE frame Current status: Dismantled ;-( Yamaha GTS1000a in Yamaha FFE frame Current status: In everyday use :-)
