I've been searching and can't seem to find a working link to instructions for the 84 and older Supras. I understand the 2.5-5v and 2.5-0v reading. I just need to know where to hook the voltmeter to. Thanks.
AJ, Thanks for the link but I already found it and it's dead. Twice actually, it's even reposted further down with missing images again. bummer. If you can forgive my lowly post count please help me with this question.
Rich64n, I have an '84. I can jump the check connector, I have a voltmeter and I'm not afraid to use it. Where do I hook it up?
I have not been able to find an 83-84 TSRM. But I'm going to guess they are the same codes as '86. Am I missing something here? If I jumper the check connector there will be no voltage from one side to the other any more. Are you saying that I should hook up the voltmeter without jumpering the check connector? or should I hook up to the check connector and to ground?
If the Check Engine light comes on and stays on during start-up, i.e. there is a malfunction code stored in the ECU memory, the needle will indicate 5 volts for 2 seconds, then indicate 2.5 volts for another 2 seconds.
After that, the number of times the needle deflects between 2.5 and 5 volts every 0.6 seconds is the first figure of the 2 digit code
Then, ditto for the second figure
If there is more than one code in the ECU, the lower number will cycle first. Then a 2.5V for 2 seconds, then the next code.
Hey I'm going to resurrect this since I still can't get my car to show any codes. Check engine light has been coming on and off more often now so there should be codes stored right? I hook up an analog voltmeter to the two pins of the check connector like rich64n said and all I get is a steady 3.5 volts. Why can't I get any codes out of this thing?