 Relay board question....., I'm missing something? |
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| Tjmrfe |
 Sep 19 2016, 09:25 AM
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#1
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NON IMPEDING RATIONE COGITATIONIS  Group: Members Posts: 132 Joined: 10-April 15 From: Cornwall on Hudson, New York Member No.: 18,612 Region Association: North East States  |
Hey Guys,
1975 1.8 F.I. (Recently purchased) I'll make it short...fuel pump isn't coming on, no voltage @ pump...so....I trace it as per (Bowlsby and my trusty F. I. Troubleshooting Manuel) and it says....check the dual relay located @ the driverside engine compartment. And there to my amazement is this ratty looking "relay board" filled with mouse droppings etc. and I think, cool!! (IMG:style_emoticons/default/biggrin.gif) This I can fix.. as per all the info I found, there should be a small round relay plugged into position #3 for the fuel pump...and......there isn't? (IMG:style_emoticons/default/WTF.gif) Only one in position #4? So....I pull it out, cleaned up the relay board, (and I replaced the fuse, which was good) and ordered a few round relays... Now, can someone tell me, is the info I found, on multiple sites wrong? Should my FP run off relay #3? And since I bought a few spares, can I keep them in the other empty relay sockets there? And does the voltage regulator relay have anything to do with this? Good thing I kept it short huh? (IMG:style_emoticons/default/dry.gif) Thanks...Terry. |
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Replies(1 - 7)
| timothy_nd28 |
Sep 19 2016, 11:32 AM
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#2
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest 
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Relays and fuses on relay board do nothing for the Ljet. Also, the only time you will see voltage at the fuel pump is when you turn the key to start, or when the flap inside the air flow meter is deflected enough to engage the fuel pump trigger
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| Tjmrfe |
Sep 19 2016, 02:18 PM
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#3
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NON IMPEDING RATIONE COGITATIONIS Group: Members Posts: 132 Joined: 10-April 15 From: Cornwall on Hudson, New York Member No.: 18,612 Region Association: North East States |
QUOTE(timothy_nd28 @ Sep 19 2016, 09:32 AM)  Relays and fuses on relay board do nothing for the Ljet. Also, the only time you will see voltage at the fuel pump is when you turn the key to start, or when the flap inside the air flow meter is deflected enough to engage the fuel pump trigger Ah ha! That explains a lot...thank you, when my key is on, there is no fuel pump voltage...that's what lead me to the relay board in the first place I'll look further. Thank you. |
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| timothy_nd28 |
Sep 19 2016, 02:42 PM
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#4
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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Have someone turn the key to start while you are measuring voltage at pin 88d at the dual relay. If you have voltage here, then you need to check the ground at the fuel pump. If you have a solid 12volts at the wires of the fuel pump, then your pump is either seized or electrically open and it's time for a new pump.
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| ndfrigi |
Sep 19 2016, 03:12 PM
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#5
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Advanced Member Group: Members Posts: 2,931 Joined: 21-August 11 From: Orange County Member No.: 13,474 Region Association: Southern California
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Terry, you're in good hand with Tim! He did help me on my 75 1.8 FI. He know all the details of it. Thanks again Tim!
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| Steve_R |
Sep 20 2016, 06:55 AM
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#6
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Member Group: Members Posts: 68 Joined: 8-August 12 From: San Diego, CA Member No.: 14,777 Region Association: None |
Hi Terry,
I attached a fuel pump trouble shooting check list. Scroll down to see the pictures. If you start at the top and work your way down you will be able to find the problem. Steve Attached File(s) 
Fuel_Pump_Trouble_shooting.pdf ( 2.76mb )
Number of downloads: 127 |
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| timothy_nd28 |
Sep 20 2016, 09:23 AM
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#7
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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(IMG:style_emoticons/default/agree.gif) this is a good flow chart. But this only works if you have a Djet
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| Tjmrfe |
Sep 20 2016, 09:50 AM
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#8
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NON IMPEDING RATIONE COGITATIONIS Group: Members Posts: 132 Joined: 10-April 15 From: Cornwall on Hudson, New York Member No.: 18,612 Region Association: North East States |
QUOTE(timothy_nd28 @ Sep 19 2016, 12:42 PM) Have someone turn the key to start while you are measuring voltage at pin 88d at the dual relay. If you have voltage here, then you need to check the ground at the fuel pump. If you have a solid 12volts at the wires of the fuel pump, then your pump is either seized or electrically open and it's time for a new pump. Thanks so much... I'm getting no voltage @ pump with key on...so, I started to back trace, and was thrown off by my not understanding that the relay board was for D jets, (IMG:style_emoticons/default/headbang.gif) I'm gonna try again with the new info. You provided. Appreciate your time..i needed exactly what you gave....the proper info. Thank you for providing that... I'll check back with the solution! |
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