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Pete, Car Enthusiast
Category: UK Car
Satisfied Customers: 24726
Experience:  Over 17 years experience diagnosing and repairing automobiles.
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Crank no start condition. The fuel pump is good I bench

Customer Question

Crank no start condition. The fuel pump is good I bench tested it . I have spark , I got it to start with starter fluid. Timing is good . All warning lights in the dash are on when key is in the on position. Coolant fan automatically comes on even though the engine is dead cold. I also keep blowing my EGI fuse. I'm thinking I have a short. Lol what am I missing
Submitted: 6 months ago.
Category: UK Car
Expert:  Pete replied 6 months ago.
Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay. I have seen in several cases before in the past when the engine cooling fan comes on like this here and you have an issue with a no start that the ecm itself may be shorted internally needing replaced.I would check for a short leading from the fuse that is shorting out here to where it runs and connects to.If there is any damage to this wiring it will need repaired.If the wiring checks out o.k. let me know the fuse number and location and I can see if I can locate what it feeds power to.You will need to have this tested further to see if the ecm needs replaced. If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.Thanks Pete
Customer: replied 6 months ago.
Thanks for the reply Pete . The fuse is #53 a 20 amp. an internal short in the ecm did cross my tmind but I'm thinking .... Really hoping it's a short and I'll tell ya why .... It's a short with one of my wires . Thanks
Expert:  Pete replied 6 months ago.
O.k.,this fuse powers these components. IPDM (most common to fail)ECM relay which feeds the ECM (in the IPDM)Throttle control relay (in the IPDM) One of these components is causing this fault here and will need tested further (usually disconnected one at a time to locate the fault but the ECM and Throtle control motor relay may be built into the IPDM with the IPDM needing replaced as an assembly) then repaired. Let me know if you need anything else and feel free to rate my help here. Thanks Pete
Customer: replied 6 months ago.
Ok Nissan decided to make my ipdm real fun lol . Mine is the type where there are no replaceable Ecm , fuel pump, and throttle body relay .they are Built into the ipdm . I forgot to mention this is a new ipdm from the dealer. After the fuse popped I checked connector E 119 terminal 7 brown wire for continuity and it gave me a high reading of 592
Expert:  Pete replied 6 months ago.
If this was a high reading between one end of the wire to the next with no other components tied into this wire or plugged in then this wire needs to be repaired at the location with high resistance or removed and replaced.If the ipdm was already replaced and did not resolve this fault here there is a chance after this wire is repaired and the fault is not corrected the ecm is at fault here needing replaced.
Customer: replied 6 months ago.
Ok what would be the best way to find out.... I had negative lead to negative post and I back probed the connector at terminal 7 , then I probed the actual wire itself with a sewing needle , don't laugh I'm not a pro lol, both gave me the same reading
Expert:  Pete replied 6 months ago.
YOu want to set the multi meter to ohms or resistance and test from one end of the wire with one lead from the meter to the other end with the other lead making sure the wire is disconnected at all components so your only testing the wire resistance itself.
Customer: replied 6 months ago.
Gotcha .... So we're not so much checking for ground but a Break or malfunction in the wire itself right?
Expert:  Pete replied 6 months ago.
Correct.If this is o.k. then take one lead of the meter and probe one end of the wire like you just had and take the other lead and probe a ground source on the vehicle and see if there is a signal to ground.It should read open circuit or OL.If it doesnt and reads a resistance signal then this wire is shorted to ground and the short needs located and repaired.
Customer: replied 6 months ago.
Do I need to refrain from using the negative post on the batt
Expert:  Pete replied 6 months ago.
No you can use that to check for a short to ground when you do the ground resistance test (the second test I had posted)
Customer: replied 6 months ago.
Ok showing no resistance from terminal 7 brown wire to terminal 111 brown wire at ECM connector. As far as I can see this wire is continuous and is not connected anywhere but these two points. Please correct me if I'm wrong lol. I'm fixing to do the other test
Customer: replied 6 months ago.
Pg 2
Customer: replied 6 months ago.
Pg 3
Customer: replied 6 months ago.
Just wanted to make sure we where looking at the same thing. Thanks for all your help by the way
Expert:  Pete replied 6 months ago.
It sounds like this wire is o.k. and the fault here is most likely the ecm needing replaced.