External fuel pump
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Thanks, Gary. That makes sense as I only have this problem when there's rain and/or dampness. Will that require a harness replacement? I was going to order one but changes my mind.
Cargo Master
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From: Somewhere n North America
Put it back together, start your engine, and check dc voltage on the STI self-test connector (100), this is the single wire (separate wire) next to the test connector. Connect Pos meter lead to STI self-test connector (100), Neg lead to the Neg battery terminal. Note voltage, should be +5 volts dc.
Last edited by vjsimone; Jul 17, 2016 at 12:44 PM. Reason: Modify text
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Unfortunately, it rained heavy last night. I'm having that starting issue with the external fuel pump running continuously. If I can get it to run normally, which at this point I can't even though it's at operating temp, I will follow through with the test. Presently, I'm stinking up the neighborhood. 
Thanks for your help!
Thanks for your help!
I have to head out soon, but I suspect you wire harness is fine. You should have little to no resistance on these wires, and your testing proves this. 40 ohms could come from your test ground connection or corrosion in the harness connectors somewhere in the path, But this is not enough to block signals from the ECA. So it would seem your computers/ECAs are not communicating with the test connector.
Put it back together, start your engine, and check dc voltage on the STI self-test connector (100), this is the single wire (separate wire) next to the test connector. Connect Pos meter lead to STI self-test connector (100), Neg lead to the Neg battery terminal. Note voltage, should be +5 volts dc.
Put it back together, start your engine, and check dc voltage on the STI self-test connector (100), this is the single wire (separate wire) next to the test connector. Connect Pos meter lead to STI self-test connector (100), Neg lead to the Neg battery terminal. Note voltage, should be +5 volts dc.
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OK. Got it running. Nothing but a 1.
I have to head out soon, but I suspect you wire harness is fine. You should have little to no resistance on these wires, and your testing proves this. 40 ohms could come from your test ground connection or corrosion in the harness connectors somewhere in the path, But this is not enough to block signals from the ECA. So it would seem your computers/ECAs are not communicating with the test connector.
Put it back together, start your engine, and check dc voltage on the STI self-test connector (100), this is the single wire (separate wire) next to the test connector. Connect Pos meter lead to STI self-test connector (100), Neg lead to the Neg battery terminal. Note voltage, should be +5 volts dc.
Put it back together, start your engine, and check dc voltage on the STI self-test connector (100), this is the single wire (separate wire) next to the test connector. Connect Pos meter lead to STI self-test connector (100), Neg lead to the Neg battery terminal. Note voltage, should be +5 volts dc.
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From: Easton,Ks
Thanks
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Yes. Seems that is not working, which explains why I can't pull codes.
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I'm off to Advanced Auto to get some more cleaner. I'll do what you suggested and get back to you.
Thanks!!
Thanks!!
Cargo Master
Joined: Jun 2013
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From: Somewhere n North America
Re-check that voltage measurement.
Mine is 5vdc, and grounding this I believe initiates the self-test.
If you don't have 5vdc, and the wire has no resistance, I would have to suspect the computer version you acquired does not match the original version.
Still need an answer to your resistance measurements ??
Mine is 5vdc, and grounding this I believe initiates the self-test.
If you don't have 5vdc, and the wire has no resistance, I would have to suspect the computer version you acquired does not match the original version.
Still need an answer to your resistance measurements ??
Cargo Master
Joined: Jun 2013
Posts: 3,176
Likes: 15
From: Somewhere n North America
Re-check that voltage measurement.
Mine is 5vdc, and grounding this I believe initiates the self-test.
If you don't have 5vdc, and the wire has no resistance, I would have to suspect the computer version you acquired does not match the original version.
Still need an answer to your resistance measurements ??
Mine is 5vdc, and grounding this I believe initiates the self-test.
If you don't have 5vdc, and the wire has no resistance, I would have to suspect the computer version you acquired does not match the original version.
Still need an answer to your resistance measurements ??
STI - (seperate connector) -
STO - (second connector from the left on the bottom row) -
SIG RTN - (top right) -
Fuel Pump - (bottom all the way to the right) -
Also be advised that disconnecting your battery will cause an unstable idle on the next start-up.
Last edited by vjsimone; Jul 14, 2016 at 08:23 AM. Reason: Adding text
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Wait, hold that as I did the test wrong. I though you wanted all four on the bottom. Hold on.
ECM and Battery Disconnected -
All 4 connections on the self-test connector register a 1.
ECM and Battery Disconnected -
All 4 connections on the self-test connector register a 1.
Oh, yeah, should have had you do this earlier; Disconnect your computer connection. Back to resistance mode; Neg. meter lead to the Neg. battery terminal. Check resistance on each self-test connector under the hood. Note all 4 readings.
STI - (seperate connector) -
STO - (second connector from the left on the bottom row) -
SIG RTN - (top right) -
Fuel Pump - (bottom all the way to the right) -
STI - (seperate connector) -
STO - (second connector from the left on the bottom row) -
SIG RTN - (top right) -
Fuel Pump - (bottom all the way to the right) -
Cargo Master
Joined: Jun 2013
Posts: 3,176
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From: Somewhere n North America
Ok, thats good, no shorts to ground. Providing you disconnected the Pos battery cable, and not the Negitive cable.
Last edited by vjsimone; Jul 14, 2016 at 10:13 PM. Reason: Editing
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Still all 1.
Oh, yeah, should have had you do this earlier; Disconnect battery. Disconnect your computer connection. Back to resistance mode; Neg. meter lead to the Neg. battery terminal. Check resistance on each self-test connector under the hood. Note all 4 readings.
STI - (seperate connector) -
STO - (second connector from the left on the bottom row) -
SIG RTN - (top right) -
Fuel Pump - (bottom all the way to the right) -
Also be advised that disconnecting your battery will cause an unstable idle on the next start-up.
STI - (seperate connector) -
STO - (second connector from the left on the bottom row) -
SIG RTN - (top right) -
Fuel Pump - (bottom all the way to the right) -
Also be advised that disconnecting your battery will cause an unstable idle on the next start-up.