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2014 Hyundai Sonata 2.4L came in on the hook, motor locked up no oil (second time for this car), replace with a junkyard unit and left the junkyard harness, replaced started because it was burned up when the customer tried to crank the engine over, now we have a no start no crank condition. I can jump the relay and crank the engine, I get control at the starter but no ground is present for the starter relay. Second I can crank with the key on and no spark. Scanned for codes and I get a pending code P1690 - Immobilizer Smartra no response. Tried to enter the immobilizer module through the scanner and it throws a no comm. So check power and ground at immobilizer?
sounds like you are missing control (-) at the relay. if you can energize the relay by providing the missing (-control) on the relay and this turns the starter on at the same time , then its definitely missing it. or are you putting 12 volts directly on the load side of the relay to energize the starter? either way, it sounds like its missing control on the starter relay.( this is normal with an anti theft issue)
my 2005 f150 also disables starter control, and injection pulse, and fuel pump, if there is an anti theft issue. The no comms suggests that things aren't talking. If the ignition key,( chip) is not being read / cleared as correct key, when you crank the key, then the pcm will recognize that you are trying to start it with out the correct key. it will then go into ani-theft mode and disable the starter and injection . when this happens it will never apply control on the starter relay during cranking.
The communication issue needs to be addressed first. Get it up and running so it can read the key , and it may need nothing else.
Patrickreaves wrote: sounds like you are missing control (-) at the relay. if you can energize the relay by providing the missing (-control) on the relay and turn the starter on, then its definitely missing it. or are you putting 12 volts directly on the load side of the relay? either way that you are doing it ,
sounds like its missing control on the starter relay.
my 2005 f150 also disables starter control, and injection pulse, and fuel pump, if there is an anti theft issue. The no comms suggests there that things aren't talking. If the ignition key ( chip) is not being read / cleared when you crank the key it will never have control on the starter relay. you need to start with the communication issue first . get it up and running so it can read the key , and it may need nothing else.
Gonna try swapping the harness in case that the donor engine was not equipped with keyless entry and other features that the original has, therefor the immobilizer and ecu do not communicate together.
I honestly don't see how an engine, that is removed from a none key-less entry donor vehicle, and installed into a key-less entry vehichle would have any effect on the anti theft issue. I just dont see the connection between the engine/harness, and the anti theft programming.(but i could be wrong) Maybe some one else knows more and can shed light on this.
Patrickreaves wrote: I honestly don't see how an engine, that is removed from a none key-less entry donor vehicle, and installed into a key-less entry vehichle would have any effect on the anti theft issue. I just dont see the connection between the engine/harness, and the anti theft programming.(but i could be wrong) Maybe some one else knows more and can shed light on this.
Harness fixed it! Not sure why it would make a difference but I know that the engine and immobilizer communicate. A vehicle with none keyless car still has an immobilizer though right?
Its good that the harness was the right call, (never would have thought it) both cars should have a similar anti theft system.
just thinking out loud here,
in 1st scenario pcm is not communicating with anti theft components , and will not start.
in 2nd scenario, same pcm with new harness that deleted keyless entry component, and it starts
one would think that in either scenario, the pcm is not seeing what it wants to see.
in scenario #1 because the new engine was missing a component that cant be plugged in. = a no com
in scenario #2 because new harness deletes the components circuit all together. this should still = a no com, because the pcm would still not see the component.
whether the component is unplugged/missing , or if you delete that components harness, the pcm is not seeing the component in either case.
maybe someone can explain this to both of us , thanks
Patrickreaves wrote: Its good that the harness was the right call, (never would have thought it) both cars should have a similar anti theft system.
just thinking out loud here,
in 1st scenario pcm is not communicating with anti theft components , and will not start.
in 2nd scenario, same pcm with new harness that deleted keyless entry component, and it starts
one would think that in either scenario, the pcm is not seeing what it wants to see.
in scenario #1 because the new engine was missing a component that cant be plugged in. = a no com
in scenario #2 because new harness deletes the components circuit all together. this should still = a no com, because the pcm would still not see the component.
whether the component is unplugged/missing , or if you delete that components harness, the pcm is not seeing the component in either case.
maybe someone can explain this to both of us , thanks
I believe my situation is the second scenario. The code from the pcm states no response from smartra which means that it got no response with key code encryption thingy. Read the link I pasted above it gives a very good overview of the Hyundai anti theft system. After reading that I really thought about that harness
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