Tech Tip: Hyundai MIL On with DTCs Set and Fail Safe Mode, Harsh Engagement – UnderhoodService

Tech Tip: Hyundai MIL On with DTCs Set and Fail Safe Mode, Harsh Engagement

An improperly functioning input speed sensor or output speed sensor may result in the following conditions: Check Engine light on; Harsh P-R or P-D engagement shock; Transaxle in third gear fail-safe; and/or Diagnostic trouble codes.

Models affected:

1999 Sonata

2001 Elantra, Santa Fe and XG

2003 Tiburon

2005 Tucson

2006 Azera

2007 Entourage

fig. 1

Automatic transaxle DTCs: P0715, P0716, P0717, P0720, P0721 and P0722

An improperly functioning input speed sensor or output speed sensor (see Fig. 1) may result in the following conditions:

• Check Engine light on;

• Harsh P-R or P-D engagement shock;

• Transaxle in third gear fail-safe; and/or

• Diagnostic trouble codes.

 

Parts Information:

Input speed sensor: 42620-39051 or 42620-39200

Output speed sensor: 42621-39052 or 42621-39200

 

Service Procedure:

1. Using a GDS, check for DTCs in both the “Engine” and “Automatic Transaxle” menus. Record the DTC(s) and description.

2. From the GDS, select:

Vehicle > “Auto Transaxle” menu > “Current Data” > “Input speed sensor” and “Output speed sensor.” Drive the vehicle and monitor the input and output speed sensors. If the sensors show:

– Continuous output, the wiring currently has no open/shorts. Go to Step 6.

– No output, go to Step 3.

3. Check the wiring harness visually for an open circuit or short circuit to ground. Check for a pinched harness at the PCM/TCM attachment bolts.fig. 2

4. Disconnect the connectors at the input and output speed sensor and PCM/TCM. Check for bent pins or pins not fully inserted into the connector.

5. If a harness open/short is found, repair or replace the ECM control harness between the PCM/TCM and transaxle and go to Step 8. If not, go to Step 6.Fig. 3

6. P0722 only: For 2006 and later Sonata and Azera, 2007 and later Santa Fe and Entourage vehicles, check the ground bolt at the location shown in Fig. 2 below and Fig. 3. Confirm the threads are clean and the bolt is tight.

7. If the ground bolts are clean and tight, follow the repair procedures shown in Chart 1.

8. Drive the vehicle for two key-on to key-off driving cycles. If the codes:

– Do not set again, return the vehicle to the ­customer.

– Set again, go to step 8.

Chart 1
DTC       Description                    Repair Procedure
P0715    Input speed sensor         Replace input speed sensor
               – no signal       
P0716    Input speed sensor
               – range/performance
P0717    Input speed sensor
               – no signal

P0720    Output speed sensor circuit    Replace output speed sensor              
P0721    Output speed sensor
               – open/short
P0722    Output speed sensor
               – no signal

P0700,    TCM MIL request to ECM    Erase code
P1529
 

9. Exchange a PCM or TCM from a similar year and model vehicle (excluding vehicles with an immobilizer). If the codes:

– Set again, replace the control wiring harness.

– Do not set again, replace the PCM or TCM.

Courtesy of Mitchell 1.

You May Also Like

Supercharger Pros And Cons

Customers generally look to superchargers for the instant throttle response, not fuel economy.

Superchargers are synonymous with making horsepower, especially in drag racing, gaining popularity and recognition as a viable power adder. However, they’re not the best option for saving fuel.

While most automakers are currently fascinated with employing turbochargers to make up for lost horsepower due to lower-displacement engines, do superchargers have a place in the current automotive climate? Indeed, this power-adder is more commonly found in the performance arena, because it produces power at lower rpm and comes in a smaller package than a turbocharger. But there are some downsides.

Plastic Timing Chain Guides

Timing chain guides are designed to wear, but the guides are designed to last the engine’s life.

It’s Got Spark!

Why can’t you trust some spark tests?

Honda Electronic Throttle Body Service Tips

Using care and following OEM procedures will help you to avoid unnecessary parts replacement and comebacks.

Belts and Pulley Alignment

A misalignment of the plane of the belt can occur when a pulley is not parallel to the other pulleys on the belt drive system.

Other Posts

Power Window Regulator Replacement

Blindly replacing a window regulator and motor assembly may not solve a customer’s problem.

Freeze Frame Diagnostics

Freeze frame data is a “snap shot” of when the code occurs of the specific sensor PIDs.

Understanding Engine Misfire Codes

When the fuel/air mixture ignites, many factors must be met to pass a misfire monitor.

Forcing OBD II Vehicle Emission Monitors

Some vehicles have readiness issues when it comes to setting all the OBD II monitors.