Mechanics

TRANSMISSION PROBLEMS

2004 Hyundai Elantra

Transmission problem
2004 Hyundai Elantra 4 cyl Front Wheel Drive Automatic 110000 miles

I have a 04 Hyundai Elantra with 110000 miles on it. When I first start driving the car the transmission won't shift out of first gear and the check engine light comes on. I have found out that when this happens I can immediately turn the car off and turn it back on and the transmission will shift properly. Do you know what the problem is and if I will need to have the transmision replaced
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Kyletaliaferro
September 27, 2010.




Hi kyletaliaferro,

Thank you for the donation.

When the CEL indicates, it indicates an error has been detected in the engine or transmission management system. Turning the engine off and restarting is able to reset the PCM.

Get a free scan done at Autozone and let me know the EXACT trouble codes so I can get the necessary information and advise accordingly.

KHLow2008
Sep 27, 2010.
My CEL is not on anymore. Can I still go get the codes or do I have to wait till this pro lem happens again

Tiny
Kyletaliaferro
Sep 27, 2010.
You need not wait. When the CEL indicates, the error would be stored in the computer and you can retrieve the trouble code even if it is not showing now.

KHLow2008
Sep 28, 2010.
Igot error codes P1529 ( Manufactuer Specific DTC) and P0750 (shift Sol A Malfunction). So I know why my tranny is doing what it's doing but what's the other error code and how easy is it to fix?

Tiny
Kyletaliaferro
Oct 25, 2010.
DTC P1529: TCM REQUEST FOR MIL ON
Description
A communication line exists between the Engine Control Module (ECM) and the Transaxle Control Module (TCM).
The sole purpose of this communication line is for the TCM to notify the ECM to activate the Malfunction Indicator Lamp (MIL) when a serious transaxle failure has occurred.

DTC Detecting Condition


http://www.2carpros.com/forum/automotive_pictures/192750_P1529Elantra04Fig386_1.jpg



Inspection Procedures

• This is only a request from the TCM to turn the MIL ON. The fault code is stored in the TCM. The freeze frame data is stored in the ECM under the P1529 request code. Be sure to retrieve the freeze frame data before clearing code P1529 from the ECM.
• Check the transaxle system.

That means you need to rectify P0750.

DTC P0750: Low & Reverse Solenoid Valve Open Or Shorted

Description
The LR annulus gear and overdrive planetary carrier are locked to the LR brake when the LR solenoid operation.

The LR solenoid is operated at the transaxle range switch "P", "R", "N" and 1st gear.

DTC Detecting Condition


http://www.2carpros.com/forum/automotive_pictures/192750_P0750Elantra04Fig66_1.jpg



Specification


http://www.2carpros.com/forum/automotive_pictures/192750_P0750Elantra04Fig67_1.jpg



Schematic Diagram


http://www.2carpros.com/forum/automotive_pictures/192750_P0750Elantra04Fig68_1.jpg



Inspection Procedures
1. Check The DTC Of The LR Solenoid Valve

1. Connect Hi-Scan (pro) to data link connector.

2. Turn the ignition switch ON and monitor the DTC.

Is the DTC P0750 the output?

Yes: Go to next step.
No: Problem is intermittent or was repaired and engine control module memory was not cleared.

2. Check The ATF System
1. Check the automatic transmission fluid level.

Is the ATF level normal?

Yes: Go to next step.
No: Add or replace as necessary.

3. Check The LR Solenoid Valve Connector

1. Turn the ignition switch OFF and disconnect the solenoid valve connector.
2. Check that the solenoid valve connector for loose, poor connection, bent, corrosion, contamination, deterioration, or damage.
3. Is the solenoid valve connector normal?

Yes: Go to next step.
No: Repair or replace as necessary.

4. Check The LR Solenoid Valve Harness

1. Turn the ignition switch OFF and disconnect the solenoid valve connector and PCM connector.
2. Measure resistance between the solenoid valve connector terminal 6 and the PCM harness connector terminal 38.
3. Measure resistance between the solenoid valve connector terminal 10 and the PCM harness connector terminal 36.


http://www.2carpros.com/forum/automotive_pictures/192750_P0750Elantra04Fig69_1.jpg



• Specifications: below 1ohm

Is the LR solenoid valve harness normal?

Yes: Go to next step.
No: Repair or replace as necessary.

5. Replace The LR Solenoid Valve

• Use the Hi-Scan Pro to delete P0750 from memory in the PCM.
• Test drive the vehicle for two key-on the key-off driving cycles.

Does P0750 reset?

Yes: Go to next step.
No: Return the vehicle to the customer.

6. Replace The PCM

1. Disconnect the battery (-) terminal and disconnect the PCM connector.
2. Replace the PCM.


KHLow2008
Oct 26, 2010.
Do you know where I can buy the Low and Revese Solenoid becuase the Hyundai department where I live has no clue what I am talking about.

Tiny
Kyletaliaferro
Oct 26, 2010.
If you had not performed the testings, do so. The solenoids might not be faulty as the problem is intermittent. Quite often such problems are caused by wiring connection fault.

The connector at the transmission tends to collect water and over time, oxidation occurs at the connector terminals resulting in bad continuity. This would cause intermittent failure.

Show the guys at Hyundai the following diagram.


http://www.2carpros.com/forum/automotive_pictures/192750_Solenoids04elantrsFig35_1.jpg

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KHLow2008
Oct 27, 2010.
Dear Expert,

could you help me to find where are the solenoid valve and the PCM connectors located in the Hyundai elantra 2004 2.0L?

The problem (that you explained about it above) occurred with my car, and I think the reason is the water collected in the connectors.

Now the problem became bigger, when I put the Automatic gear on the D position, there is no response and car deosnt move( as N position) in addition to the check engine leds is on all the time.

Kindly waiting for your reply.
Thank you.

Tiny
Omara
Dec 26, 2013.

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