Fix code P0335 and P1372 Hyundai Santa FE no start,
P0335 Crankshaft Position Sensor (CKP) Circuit Malfunction and P1372 Segment Time Acquisition Incorrect. In layperson’s terms, the P1372 is a misfire. But don’t start replacing spark plugs and ignition coils yet.
The engine computer detects cylinder misfires by monitoring the “rate of revolution” using the CKP. If the computer commands the spark plugs and injectors to fire, it expects to see crankshaft rotate at a predictable rate, with each cylinder contributing power to the rotation. However, if a cylinder misfires, the crankshaft slows down slightly because the misfiring cylinder didn’t contribute to engine power. So it makes perfect sense that if you have a bad CKP, you might get a P1372 at the same time.
Shops report a fairly high failure rate on this sensor. So you can take your chances and replace it (the part runs about $50), or you can do the tests below. The choice is yours. But keep in mind the part is NOT returnable–so you replace it at your own risk.
A shop would connect a digital oscilloscope to the CKP and check the high/low voltage patterns as the engine cranked. Since you probably don’t own a scope, you can only perform a few basic voltage checks to test the integrity of the wiring harness. First, find the CKP sensor on the front of the engine (driver’s side) and follow the wires from the sensor to the “joint electrical connector” at the front of the engine compartment. Disconnect the CKP connector and turn the key to ON. Check for battery voltage on the yellow wire at the joint electrical connector connector. If there’s no voltage, search for an open near the connector or trace the circuit backwards. Next, set your digital volt-ohm meter (DVOM) to ohms and check for a short to ground on the pink and white wires in the disconnected CKP wiring harness. If you get anything other than an “infinite” reading, you’ve got a short-to-ground. Reconnect the CKP connector and turn the key to ON again. Backprobe the pink wire, and check for 5-volts DC. Backprobe the white wire and check for ground. If you get all those readings, it certainly appears that the CKP is bad. But again, only a scope can confirm that.
© 2012 Rick MuscoplatPosted on by Rick Muscoplat