No Start, 1972 914 will not start |
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No Start, 1972 914 will not start |
Mike1981 |
May 20 2018, 05:25 PM
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#21
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Member Group: Members Posts: 212 Joined: 21-July 14 From: Detroit MI Member No.: 17,663 Region Association: Southern California |
The relay/circuit board in the engine compartment is just a pass through for the started circuit, none of the relays on the board have any impact on the started circuit. When you are checking for voltage at pin 1 of the 14 pin connector and then again at pin 6 of the 12 pin connector, are the harnesses unplugged or are you back probing the connectors? Some time a connection can be just strong enough to carry the small voltage of an ohm meter but looses connection with more voltage or load. Also some time the physical force of a connector moves thing enough to break a connection. You can also test for voltage at the circuit through the panel by testing at T2 (II) or T4 (IV) of the FI socket on the board, both of them are tied to the same circuit. If you apply power to the wire at pin 6 of the 12 pin connector does the starter crank? Jim Hello Jim I tested for voltage on T2 and T4 no voltage but I did notice that if I place the negative test probe on T2/T4 and touch the other end to ground I get a beep on my tester, Could this indicate a short to ground on the relay board? Also applied 12VDC from a seperate battery Plus on T2 and T4 Neg on door keep I heard a relay click no start |
Mike1981 |
May 20 2018, 06:11 PM
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#22
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Member Group: Members Posts: 212 Joined: 21-July 14 From: Detroit MI Member No.: 17,663 Region Association: Southern California |
OK Had an Idea.
I disconnected the 14 pin harness jambed a wire into pin 1 crimped on a spade connector and stuck it onto the S terminal on the starter. When I turned the key the starter cranked! However I noticed the fuel pump was not humming and I believe there is one relay that controls the fuelpump on this board. Is this the case? |
Mark Henry |
May 20 2018, 08:29 PM
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#23
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I am sorry to tell you now that the seats slide off the rails: you don’t have to unbolt them. Did you disconnect the seat wire or did you find it that way? Thanks Yes they do slide forward but I was looking for a relay under the seat and needed the room. I found it disconnected I will cut it off and jump the leads together. Thanks There's a little spring stop on the one seat rail, press it and the seat slides forward right off the rails. Then you can you pull the seat right out of the car in seconds. Hard to feel, first few times you have to get a flashlight and look down the front of the rail to see how it works. |
jcd914 |
May 20 2018, 11:17 PM
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#24
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
In these pictures there is no seat belt interlock relay just the connections for the seat belt light. So it appears your car does not have an interlock relay,
And since your test with a wire from T1 to the starter make it crank you are getting enough power from the ignition with to the engine comp relay panel. Jim |
jcd914 |
May 20 2018, 11:28 PM
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#25
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
OK Had an Idea. I disconnected the 14 pin harness jambed a wire into pin 1 crimped on a spade connector and stuck it onto the S terminal on the starter. When I turned the key the starter cranked! However I noticed the fuel pump was not humming and I believe there is one relay that controls the fuelpump on this board. Is this the case? DISCLAIMER: When I wrote this I forgot the car was a V8 conversion, so my testing recommendations are following the stock wire configuration and there may have been changes made during the conversion that make the circuits different. This was a good test. It show the circuit from the battery to the ignition switch and back to the 14 pin connector works. Now you need to figure out why power stops there. Since you disconnected the 14 pin connector for this test the fuel pump won't run. As another quick test you could hook the starter back up as normal, yellow wire to the S terminal. Then take and unplug both the 12 pin and the 14 pin and make a jumper wire to go from T1 of the T14 connector to T6 of the T12 connector and then crank it from the key. This would bypass the relay board. If this works the engine will crank over but it won't start since the T12 and T14 connector are disconnected. Have you verified that the yellow wire is in position 6 on the T12 connector? Have you checked over the relay board? Take out out and turn it over, what does it look like? Jim |
Mike1981 |
May 22 2018, 06:58 PM
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#26
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Member Group: Members Posts: 212 Joined: 21-July 14 From: Detroit MI Member No.: 17,663 Region Association: Southern California |
OK Had an Idea. I disconnected the 14 pin harness jambed a wire into pin 1 crimped on a spade connector and stuck it onto the S terminal on the starter. When I turned the key the starter cranked! However I noticed the fuel pump was not humming and I believe there is one relay that controls the fuelpump on this board. Is this the case? DISCLAIMER: When I wrote this I forgot the car was a V8 conversion, so my testing recommendations are following the stock wire configuration and there may have been changes made during the conversion that make the circuits different. This was a good test. It show the circuit from the battery to the ignition switch and back to the 14 pin connector works. Now you need to figure out why power stops there. Since you disconnected the 14 pin connector for this test the fuel pump won't run. As another quick test you could hook the starter back up as normal, yellow wire to the S terminal. Then take and unplug both the 12 pin and the 14 pin and make a jumper wire to go from T1 of the T14 connector to T6 of the T12 connector and then crank it from the key. This would bypass the relay board. If this works the engine will crank over but it won't start since the T12 and T14 connector are disconnected. Have you verified that the yellow wire is in position 6 on the T12 connector? Have you checked over the relay board? Take out out and turn it over, what does it look like? Jim Hello Jim Took Our relay board Removed black backing All Traces looked good to me and ohmed out Going to keep testing board Any Suggestions?? https://www.facebook.com/photo.php?fbid=225...e=3&theater |
Mike1981 |
May 22 2018, 06:58 PM
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#27
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Member Group: Members Posts: 212 Joined: 21-July 14 From: Detroit MI Member No.: 17,663 Region Association: Southern California |
Anyone with any ides thanks
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Mark Henry |
May 22 2018, 08:51 PM
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#28
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
The connector main harness plug in to relay board, disconnect it, pop the back off the connector, look for the yellow wire and test it (turning key) at that point.
If it doesn't work next stop is ignition switch, then power to switch, fuse block, etc. |
jcd914 |
May 22 2018, 11:06 PM
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#29
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
OK Had an Idea. I disconnected the 14 pin harness jambed a wire into pin 1 crimped on a spade connector and stuck it onto the S terminal on the starter. When I turned the key the starter cranked! However I noticed the fuel pump was not humming and I believe there is one relay that controls the fuelpump on this board. Is this the case? DISCLAIMER: When I wrote this I forgot the car was a V8 conversion, so my testing recommendations are following the stock wire configuration and there may have been changes made during the conversion that make the circuits different. This was a good test. It show the circuit from the battery to the ignition switch and back to the 14 pin connector works. Now you need to figure out why power stops there. Since you disconnected the 14 pin connector for this test the fuel pump won't run. As another quick test you could hook the starter back up as normal, yellow wire to the S terminal. Then take and unplug both the 12 pin and the 14 pin and make a jumper wire to go from T1 of the T14 connector to T6 of the T12 connector and then crank it from the key. This would bypass the relay board. If this works the engine will crank over but it won't start since the T12 and T14 connector are disconnected. Have you verified that the yellow wire is in position 6 on the T12 connector? Have you checked over the relay board? Take out out and turn it over, what does it look like? Jim Hello Jim Took Our relay board Removed black backing All Traces looked good to me and ohmed out Going to keep testing board Any Suggestions?? https://www.facebook.com/photo.php?fbid=225...e=3&theater Since your earlier test (jumper from T1 to the starter) showed power from the ignition switch to the wire at T1 of the T14 connector, I would be looking at the rest of the circuit. My next step might be to swap in a different relay panel but I have at least 3 of them that I know if. Did you try jumping from T1 if the T14 connector to T6 of the T12 connectors? Did the starter cranks? You can also jump power from the battery directly to T6/T14 and see if it cranks. If it does I would then plug in T12 and unplug T14 and jump from the battery to T1/T14 on the fuse panel, this would test power flow through the panel. On the fuse/relay panel traces, the traces all run on the bottom and if fried you can see it but they all connect to the pins and connectors going to the relays and connectors on top of the board. It is the connections from the traces to the connectors that are problematic. Corrosion or a loose connection can show good with and ohm meter but still not be able to carry the load of the circuit. I don't know how many amps a starter solenoid draws bur it is significant. Jim |
Mark Henry |
May 23 2018, 05:09 AM
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#30
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I didn't see you already tried what I suggested and it's a relay board issue.
My /6 conversion I removed my relay board. To do this you can get a connector to DIY a harness or get custom engine harness from member Perry Kiehl. |
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