View Full Version : 1990 Code 69 Fault Code

07-18-2007, 11:32 AM
Just re-built a 1990 Classic, put it all together and I am getting a Check Engine fault code 69. I have replaced the neutral park switch, which works perfect. Starts in neutral/park and not in gear. The reverse lights go on in reverse. Performed the Continuity Test 24 although I did it with the plug detached from the ECUnit at the junction below the passenger side firewall. The test read 0 ohms in gear and 122 ohms in park/neutral. I tried counting #34 on the plug middle bottom row, but the results were not consistant. Frustrated because truck works fine, but I can't clear this code. I have went through the general process to clear fault codes but it keeps appearing.


1.Am I counting the right number in the ECU plug?

XXX_XX... X's = plugs

I started counting at first plug by the blank as row 1, left to right then read each row left to right. Resulting in #34 on the bottom 3rd row.

Any other opinions would be greatly appreciated, want to get this truck registred, need check engine light off for emissions. Thanks Doug

07-19-2007, 11:11 AM
Sometimes just posting gets you thinking. Took apart ECU plug, checked ohms at orange/black = L. Examined ecu cable and sure enough found a small slice, removed tape and out of 40 some wires the orange/black was sliced in two. Fixed the slice and sure enough the Check Engine was off. Doug