SureTrack Community Fix: Not So Smart Key Kia

Real Fixes from Mitchell 1’s SureTrack® expert information resource are documented issues from actual shop repair orders and community discussions. Read on to see how SureTrack can help you correct issues that are not easily diagnosed using OEM information alone. SureTrack is available at no additional cost in our ProDemand product.


It’s always a risk trying to fix a car that the owner worked on themselves first and now is broken. SureTrack community member sleazen had a Kia Optima in their shop that the customer swapped the engine in and now won’t start. They replaced the pump but that didn’t fix it. They posed the question to the community, and with the help of fellow community member todawg and others, they were able to resolve the issue quickly.

The following Community Fix summarizes the interaction between members of the community that led to the solution.

Vehicle
2015 Kia Optima LX 2.4L

Title
Engine won’t crank, replaced wiring harness.

Complaint
Customer states that starter will not engage with ignition switch after engine replacement.

Diagnostic Steps Performed/Parts Replaced
Customer replaced engine with a used one. No codes stored. Power to all related fuses OK. Power and constant ground are normal at starter relay. Starter can be engaged by jumping the power-to-starter circuits at the relay. There is no crank signal getting to the relay from the ignition switch.
The only component left untested in the circuit is a Burglar Alarm Relay which, according to the only wiring diagram with an ignition switch, is positioned between that fuse and the starter relay. All testing is assuming WITHOUT Smart Key (which this key appears to be since it’s a switch-blade type in a fob), because everything points in that direction, such as the starter relay control circuit going to permanent ground. However, the diagram WITH Smart Key doesn’t have an ignition switch; only a push button start switch. Is there a way to tell, definitively, whether or not I have a Smart Key system of any type?

Best Answer from Community Member todawg
I would say it’s with out smart key if no push button. Do you have start power going to the P/N switch?

Cause
Customer had bought and installed a used engine WITH loom. Turns out the assembly came out of a car with push button start. That’s why the neutral switch wires were not in the correct cavities of that connector. Fortunately – for him – he still had it all at home. Brought it in and I grabbed the entire loom off the old engine.

Correction
Installed original wiring loom and car now starts as it should.


SureTrack® adds to the power of ProDemand® with an exclusive combination of real-world knowledge and powerful diagnostic tools, all wrapped in an interactive community of professional technicians. Designed to help automotive shops increase accuracy and efficiency from diagnosis to completed repair, the industry’s most comprehensive repair information resource is just a few clicks away.

Want more? Here’s how you can see more Real Fixes in SureTrack:

About the Author

Nick Taylor

Nick Taylor is the SureTrack Community Administrator and a Senior Applications Specialist at Mitchell 1 with over 25 years of experience with electronic repair data systems. Nick previously worked in the automotive dismantling and engine rebuilding industries.