How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask IKIA21 Your Own Question
IKIA21
IKIA21, ASE Certified Technician
Category: Kia
Satisfied Customers: 25
Experience:  I have 10 years experience working on many models. I specialize in Kia, Hyundai, and Mazda.
9080169
Type Your Kia Question Here...
IKIA21 is online now
A new question is answered every 9 seconds

Kia Sorento with 4 wheel drive problems.

Customer Question

2003 Kia Sorento has  four wheel drive problems. The 4 LO light is always illuminated and it is in 2 HI. I'm an auto mechanic, double master certified with both advanced levels. I'm not looking for a random guess. I bought the car off of an individual who threw every part under the sun at it.

Since then I have voltage drop tested, every wire amp-load tested with a headlight and OHMed to power. Ground and to every other wire in harness, everything tests fine, but I have no data path or trouble shooting information, nor can I find a correct way to read or clear codes.

However, I can disconnect shift motor, energize it and shuttle in to 4 LO then I can plug it back in and use the mode selector and it will shuttle to 4 HI if I want and then if I choose I can shuttle to 2 HI if I want. But 4 LO light is always illuminated and then that is it. If I want to shift again I have to go through the whole process again. With suspension the TCM was inputting incorrectly, I unplugged it.

Submitted: 9 years ago.
Category: Kia
Expert:  IKIA21 replied 9 years ago.

Hello!

I will try to help you out here! I have been working on these for a long time! It is tough because you don't have the code but I will do my best!

The driver determines operation mode (2WD, 4WD HIGH, 4WD LOW) using a selector switch. 2H MODE : Rear wheel operating mode. 4H MODE : It is possible to change between 2WD and 4WD during driving while vehicle speed is below 80Km/h. When shifting completes, 4WD HIGH lamp is turned ON. 4L MODE : It is possible to change to 4L mode while vehicle speed is below 3Km/h. ("N" position with AT vehicle. Clutch switch "ON" with MT). When shifting completes, 4WD LOW lamp is turned ON.

DTC Description

The 3 position switch provides ground to the ECU inputs. There are 2 inputs 2/4 and high/low. The 2/4 input is tied to the 2H switch position and the high/low input is tied to the 4L switch position. If the switch is in the 2H position it provides ground to the 2/4 input. If the switch is in the 4L position it provides ground to the high/low input. If the switch is in the 4H position both of the ECU inputs (2/4 and high/low) are high. It is not physically possible for the switch to provide ground to both the 2/4 and high/low input at the same time.

When 5 volts from TCCU is inputted into MPS case, mode switch changes, shift motor operates, and MPS contact point is either ON or OFF. When 5 volts is inputted into TCCU, TCCU monitors operation of shift motor. There are 4 digital inputs for the shift motor position sensor. These 4 inputs, used in various combinations, make 16 possible Gray codes. The sense plate does not use all of these codes and non-used codes are considered invalid.

DTC Description

This trouble code is set when the Motor Position Sensor detects a mapped value in the TCCU that is different from the actual input value.

Shift motor is controlled by TCCU and motor is rotated by the selecting of mode switch. Accordingly, the 4WD function is operated by controlling the reduction and forkup forks using the shiftshaft and shiftcam. 2H →4H →4L Mode : Terminal 7,8 (B+) / terminal 22, 23 (Earth) 4L → 4H → 2H Mode : Terminal 122, 23 B(+) / terminal 7, 8 (Earth)

DTC Description

The shift motor's H-Bridge circuit uses high side driver chips with status lines for indicating faults.

1.Ignition OFF.
2.H-14 TRANSFER SOLENOID & MOTOR connector : Disconnect.
3.Measure resistance between 6 & 7.
a.Specification : Approx. 0.78±0.078?

The above value is only for reference. The data from vehicle may differ from it according as various vehicle condition. This inspection is for checking open or short of Shift Motor.
4.Is resistance display near the specified value?
YES
a.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
b.Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
a.Check "Shift Motor" for contamination, deterioration, or damage.
b.Substitute with a known-good "Shift Motor" and check for proper operation. If the problem is corrected, replace "Shift Motor" and then go to "Verification of Vehicle Repair" procedure.
1.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
a.Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
a.Go to " Position Encoder Signal Inspection " procedure .
Position Encoder Signal Inspection
4.Engine : Idling.
5.TCCU connector : Connect.
6.Measure resistance between terminal 12,4,18,19,21 of TCCU connector H-08 and chassis ground .
7.Select Mode Switch to 2H →4H → 4L Mode.
a.Specification : Signal Waveform

The above value is only for reference. The actual value may differ from it according to various engine condition.
8.Is Position Encoder display near the specified value?
YES
a.Fault is intermittent caused by poor contact in the sensor's and/or TCCU's connector or was repaired and TCCU memory was not cleared.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
a.Go to " Position Encoder harness short circuit to ground inspection " procedure.
Position Encoder harness short circuit to ground inspection
9.Ignition ON,
10.TCCU connector : Disconnect.
11.Measure resistance between terminal 12,4,18,19,21 of TCCU harness connector H-08 and chassis ground .
a.Specification :Approx. ∞?.

The above value is only for reference. The actual value may differ from it according to various engine condition.
12.Is resistance display near the specified value?
YES
a.Go to " Position Encoder open circuit inspection " procedure .
NO
a.Check for short to ground circuit of Position Encoder signal harness.
b.Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
Position Encoder open circuit inspection
13.Ignition OFF.
14.TCCU connector : Disconnect.
15.Measure resistance between terminal 12,4,18,19,21 of TCCU harness connector H-08 and 1, 2, 3, 4 ,5 of TRANSFER SOLENOID & MOTOR harness connector H-10 .
a.Specification : Approx. 0 ?

The above value is only for reference. The actual value may differ from it according to various engine condition.
16.Is resistance display near the specified value?
YES
a.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
b.Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
a.Check for open Position Encoder harness .
b.Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
Customer: replied 9 years ago.

I double and triple checked the encoder circuitry and the person I bought it from has three different shift motors with veh. and 3 tccms. I checked operation of switch at tccm. and only one wire was grounded at a time otherwise it had 5 volts except for in 4 HI (I think) then both wires had reference voltage.

I noticed it has no overdrive unless the tccm is unplugged and then trans. works fine. Why is this thing not doing any blink codes? Is it not meeting code setting criteria and is there any other test you can offer? What is clearing proc. ground pin,12?

Expert:  IKIA21 replied 9 years ago.

You should be able to clear it by unplugging the battery. It is really tough to diagnose further without the code!

You should consider taking it to the dealer.