NEED HELP!, D-Jetronic Wiring Harness plug into relay board |
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NEED HELP!, D-Jetronic Wiring Harness plug into relay board |
Beebo Kanelle |
Apr 14 2019, 09:09 PM
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#1
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Member Group: Members Posts: 248 Joined: 22-November 12 From: Houston, Texas Member No.: 15,177 Region Association: Southwest Region |
The Wiring harness for the D-Jetronic utilizes a 4 - pole connector to plug into the 4 - pole scoket on the relay board.
Does anybody know the specific purposes for each of the connections? On the relay board diagram, they are labeled I, II, III, IV. I appears to be switchable power from the relay from the power supply. II appears to be Switched power supply bridged with IV? III appears to be the fuel pump signal IV appears to be Switched power supply bridged with II? Can anybody explain the design functions / purpose for each of these poles? Thank you in advance. |
JamesM |
Apr 15 2019, 12:41 AM
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#2
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Senior Member Group: Members Posts: 1,915 Joined: 6-April 06 From: Kearns, UT Member No.: 5,834 Region Association: Intermountain Region |
Mostly right, but what specifically are you looking for/looking to do?
III when grounded activates the fuel pump relay, the rest as you mentioned are 12v supplied to different circuits of the d-jet system. Though if memory serves me correctly II and IV are powered via the starter circuit (but dont quote me on thats, its been a while since i messed with this stuff. You can see where the pins "go" here http://bowlsby.net/914/WiringHarnesses/HarnDia_FI_GA.jpg but if you want to know exactly what they do buckle up and get ready for some serious reading... https://members.rennlist.com/pbanders/ecu.h...CU%20Schematics The links to Sheet 1- Sheet 3 break down the internal circuits of the ECU. IF I have understood this correctly in the past... "I" (relayed power) on the relay board are wires/pins 16 and 24 on the D-jet ECU that are primarily powering the injector drivers and triggering mechanisms. "IV" (wire 31) provides 12v to the CSV under cranking, the other side of the CSV is then wired to the thermo time switch. "II" tied to "IV" goes to Pin 18 on at the ECU though I dont recall exactly what it does. I think it was tied to part of the ECUs fuel pump control logic. The Wiring harness for the D-Jetronic utilizes a 4 - pole connector to plug into the 4 - pole scoket on the relay board. Does anybody know the specific purposes for each of the connections? On the relay board diagram, they are labeled I, II, III, IV. I appears to be switchable power from the relay from the power supply. II appears to be Switched power supply bridged with IV? III appears to be the fuel pump signal IV appears to be Switched power supply bridged with II? Can anybody explain the design functions / purpose for each of these poles? Thank you in advance. |
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