"Check short to battery in signal harness."

[eratus]

Hi all, I've been trying to get my mom's car running... true nightmare. It's a 2004 Hyundai Santa Fe 2.4L Auto 2wd. Stopped running, got error code for crankshaft sensor. Replaced, still no start. Have gone through everything related and narrowed it down to the wiring harness going to the sensor.
The following procedure yielded the problem:
Check for short to battery in harness (1) Ignition "OFF" (2) Disconnect CKPS connector (3) Measure resistance between terminals "2" and "3" of CKPS harness connector. A.
Specification : Infinite
[See large image...] (4) Is the measured resistance within specifications?
YES ▶ Go to " Check for open in harness " as below.
NO ▶ Check short to battery in signal harness. ▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
I do not get infinite resistance between the two terminals of the connector. So now the question is, how do I "Check short to battery in signal harness"?


UPDATE: Terminal 2 is the signal wire, terminal 3 is the power wire. Somehow, the two are shorted together. I attempted a work around without having to tear apart the whole wiring harness. I cut the signal wire at the connector and at the ecu. I then spliced in a fresh wire, for a direct connection between the two. Still no spark, and I STILL show a closed circuit between terminal 2 and 3! So i disconnected the splice at the connector under the hood and checked to see if the connector was bad, but NO, I get infinite resistance! So the connector is good, the wire is good, and I already replaced the ecu. WTF!?



I need some help before I go insane.

[sbr711]

Timing belt cut the sensor harness because it did not get tucked back into the slot/ear of the front block cover there by the oil pump drive cog out of reach of the timing belt...

Been there // done that

[eratus]

Sorry if I wasn't clear. The short is in the harness that the connector from the Crank sensor plugs into. So the test I've done is with the sensor unplugged. I'm checking the wires that go to Power/Ground/ECU, not the sensor itself.

Here is the complete list I was working my way down. Everything was fine until the last one:

Terminal and Connector Inspection1.Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3.Has a problem been found?
YES
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO
▶ Go to " Power Circuit Inspection " procedure.
Power Supply Circuit Inspection1.Check Power Supply
(1)Ignition "OFF"
(2)Disconnect CKPS connector.
(3)Ignition " ON " & Engine "OFF"
(4)Measure voltage between terminal "3" of CKP sensor harness connector and chassis ground.
Specification : B+

(5)Is the measured voltage within specifications?
YES
▶ Go to " Check CKPS Power " as below.
NO
▶ Check open or short to ground in harenss between control relay and CKPS.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
2.Check CKPS Power
(1)Ignition "OFF"
(2)Disconnect CKPS connector.
(3)Ignition "ON" & Engine "OFF"
(4)Measure voltage between terminal "2" of CKPS harness connector and chassis ground.
Specification : 5V

(5)Is the measured voltage within specifications?
YES
▶ Go to " Component Inspection " procedure.
NO
▶ Go to "Signal Circuit Inspection" procedure.
Signal Circuit Inspection1.Check for short to ground in harness
(1)Ignition "OFF"
(2)Disconnect CKPS connector and PCM connector.
(3)Measure resistance between terminal "2" of CKPS harness connector and chassis ground.
Specification : Infinite

(4)Is the measured resistance within specifications?
YES
▶ Go to " Check for short to battery in harness " as below.
NO
▶ Check short to ground in signal harness.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
2.Check for short to battery in harness
(1)Ignition "OFF"
(2)Disconnect CKPS connector
(3)Measure resistance between terminals "2" and "3" of CKPS harness connector.
A.Specification : Infinite

(4)Is the measured resistance within specifications?
YES
▶ Go to " Check for open in harness " as below.
NO
▶ Check short to battery in signal harness.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.

[paul03]

Hi,
I understand you replaced the harness wires by external wires. Good show.
If you check the wires by the check specifications, you must be shure to only measure the wires, not the rest.
So you must detach the connectors on both sides from their parts, being at the sensor and at the ECU.
By replacing the wires you are only left with the remaining connectors, being of possible fault sources. There are only 3 (2) wires, so it is an easy check. If there remains a residual resistance between open wires, it can only be because of the connectors. Maybe dirt, moisture, oil, chemicals.
Depending the resistance, infinite can be seen as a lot of Mohms.
I suppose, the voltage at the power supply connection is 5 volts, so you can also measure the voltages at the sensor, being 5 volts and
(no sensor attached) 0 volts at the signal terminal. Also check the ground terminal at the sensor side. Sometimes ground isn't that firm, so the output signal of the sensor will be floating and the ECU will not read correctly.
If you attach the connector(s) you are measuring the parts, the ECU and/or the sensor resistances.
Good luck,
Paul

[eratus]

So far I've only replaced the signal wire. I assume it goes directly from the sensor connector to the ecu connector pin 5. I was able to verify the correct pin. I assume the ground wire goes to a ground under the hood, and the power wire goes somewhere in the fuse box. I haven't been able to locate a wiring diagram in the manual. Is it possible the 12v power wire also goes to the ecu? Because I've already checked the plug at the other end, and I just assumed only the signal wire was going to the ecu connector.

[paul03]

I was a bit mistaken. power wire is +12 volts battery and signal wire has 5 volts signal.
But they all go to the ECU, not to another ground and battery at the engine.
I suppose that's done for possible bad loops if connected elsewhere.
That's also done with other sensors, all wires to the ECU.
However, you could measure the voltages 12 volts battery and 5 volts signal. And ground must be grounded.
Best to measure it with oscilloscope, you can see variations in signal.
Maybe you can search for all schematics at hmaservice.com.
Good luck,
Paul