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92 Accord Blinking D4 (TCM Error codes needed)

Discussion in 'Accord' started by Easy Duzit, May 8, 2009.

  1. Easy Duzit

    Easy Duzit New Member

    Likes Received:
    May 8, 2009
    Hello All. I've spent hours on this and am getting a bit frustrated. This happens only in hot weather. The car starts and runs fine until I turn it off. Then it won't start again and the D4 light blinks. This has been a consistent issue even after replacing a bad trans last year, but has gotten worse lately. I've spent the time and researched this online, and found the likely causes for not starting in hot weather, are either the main relay (bad solder joints), or a bad transmission control unit ( TCM ). Since the D4 light is blinking, I'm leaning towards the tcm. But I wanted to check the error codes.
    So I cleared the error codes by removing the main fuse, then started it and drove it a few miles. Turned it off, waited 5 minutes, and tried to start it, and of course it didn't start, but the D4 light started blinking (which I expected). So I shorted the service check connector, and checked the tcm diagnostic codes by counting the blinking D4 light. It gave me 4 separate error codes. 1 blink, 2 blinks, 7 blinks, then 8 blinks.
    Heres whats driving me crazy. The only error codes I can find anywhere are for the ecu, NOT the tcm, and the 4 codes I have don't make any sense with regard to the tcm preventing the car from starting. If I use the ecu codes (1, 2, 7, 8 ) they are for:
    1 O2A - Oxygen sensor #1
    2 O2B - Oxygen sensor #2
    7 TPS - throttle position sensor
    8 TDC - top dead centre sensor - Non of which is transmission related. I mean, If these codes were correct, wouldn't the check engine light be on instead of the blinking D4 light?

    As for the check engine light, it only comes on briefly when I start the car, which is normal, and has never come on while driving, and it never comes on when the car doesn't start from this problem. Only the D4 light blinks. So I know the codes are from the tcm not the ecu. If I clear the codes and then start the car, it will run perfect for hours at a time, until I turn it off and try to restart it. So those error codes which apply to the ecu can't apply here, because it just doesn't make sense. I mean, if those codes are correct, the car would't run fine when I did start it. Would it?
    So I need to know what the tcm diagnostic codes are, not the codes for the ecu. It has to be a seperate set of codes but I can't find them anywhere. Every post on this forum asking for tcm codes has been referred to the ecu codes, but again, that doesn't make sense. I'm not a mechanic, but it seems that there should be a different set of codes for the tcm and the ecu. Help.....

    As it stands, I'm getting ready to pull the tcm and swap it out, since that is a known problem in hot weather, but I would still like to find the correct codes. Any help or ideas here are greatly appreciated. Especially if you can give me the actual tcm codes:)

    Easy Duzit
  2. Frank Allen

    Frank Allen New Member

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    Aug 12, 2008
    new caney texas
    92 accord

    I had the same problem, i took the car to a mech, he said nothing wrong with oxegen sensor but the ports needed cleaning out, i had no check engine light, after he did that it cleared the code but still had the blinking d-4 light and the starting problem, after reserch and study i found that the main realy supplies a voltage to the tcu, a bad realay and poor solder joints at the pig tail of the main relay caused the car not to start when hot , also caused the tcu to malfuntion , i put a new relay in and resoldered the pigtail, had to also replace the tcu, be sure to get the right number, some of the early tcu,s were prone to failure PXO 721 for dx and lx, ex and se are different and will not work, also has to come from a 92 or 3, 90- 91 will not work, in some later 92 models had a PXO 722 which is what i got from a junk yard and its perfect, the car shifts and starts fine now. hope this info is helpful. . there are a lot of tcu,s from 90 to 93 that all look alike and will plug in but will not perform correctly so watch the number,s
    Frank Allen
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