Pins missing from ECU connector?

[Yellow Van]

I'm working on the FI system on a California 1981 Vanagon and I read L-Jetronic manual page 26 that indicates testing of terminal 3 and 18 on the CPU connector. When I tried to do this, I discovered that space 18 is just empty in the connector! Am I missing something important or can there be a variation without this connector pin?

[glutamodo]

I vaguely remember running into this from when I was a mechanic. The Bentley has a chart of checks on the EFI wiring that also shows to test that switch from 3 to 18.... but when you turn to the wiring diagram that shows the ECU it shows no terminal 18 present. Instead it goes to the oxygen sensor relay, which is powered via the coil and the double relay, and then sends its signal via that switch into the brain at terminal 3, if I'm interpreting that diagram correctly. The wire gauge happens to be 18 though, and I remember wondering if someone misread that on the wiring diagram at some point and this caused other charts/procedures to be wrong, and no one caught it.

[monstersteve]

This was a source of frustration for me. After taking the ECU harness apart to see if a pin dropped (it didn't), I did some research. The Bentley manual (and same for the AFC manual) should read that your multimeter leads go to #3 on the ECU and #8 on the OXY sensor (enrichment module) terminal #8. That will give you your diagnostic information.

[Abscate]

Good sleuthing !!

Famous saying " the prudent mariner never relies on a single source of information for navigation"


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.ssS!