Fix P2738: STEP-BY-STEP diagnostic GUIDE!

The P2738: Pressure Control Solenoid ‘F’ Control Circuit Low refers to a condition where the voltage in the control circuit for pressure control solenoid ‘F’ is lower than expected. This can result from a faulty solenoid, damaged wiring, or an issue with the control module, potentially causing improper regulation of transmission fluid pressure.

P2738 – Quick Overview

CodeInformation
MeaningP2738: Pressure Control Solenoid ‘F’ Control Circuit Low
Is it serious?Yes, this issue can result in poor transmission performance, including shifting problems and increased wear on transmission components.
Possible causes– Low voltage in pressure control solenoid ‘F’ control circuit
– Faulty solenoid or wiring
– Control module issues
How to diagnose?– Measure voltage in pressure control solenoid ‘F’ control circuit
– Inspect wiring and connectors
– Check for shorts or damage
– Replace components as needed

P2738 Meaning

The P2738: Pressure Control Solenoid ‘F’ Control Circuit Low code indicates that the voltage level in the control circuit of pressure control solenoid ‘F’ is lower than the acceptable range. This may be caused by a faulty solenoid, damaged wiring, or a problem with the control module that affects the signal being sent to or received from the solenoid. Such a condition could lead to irregular hydraulic pressure control within the transmission and impaired shifting performance.

Step-by-step diagnostic guide

ActionDescriptionTools Needed
Check for Other CodesUse an OBD-II scanner to check for additional codes that may provide further information or context for diagnosing the voltage issue.OBD-II Scanner
Measure Voltage in Pressure Control Solenoid ‘F’ CircuitUse a multimeter to measure the voltage in the control circuit for solenoid ‘F’. Compare the measured voltage to the manufacturer’s specifications to determine if it is too low.Multimeter, Vehicle Owner’s Manual
Inspect Wiring and ConnectorsVisually inspect the wiring and connectors leading to solenoid ‘F’. Look for signs of wear, damage, corrosion, or loose connections that could cause a drop in voltage.Flashlight, Safety Gloves
Check for Shorts or DamageInspect the wiring harness for any signs of shorts to ground, cuts, or breaks that might lead to low voltage. Carefully examine areas where the wires might be pinched or rubbed.Multimeter, Flashlight
Test Control Module SignalVerify that the control module is correctly sending signals to solenoid ‘F’. A malfunction in the control module could result in low voltage to the solenoid.Diagnostic Tool, Manufacturer Software
Replace Faulty Components as NeededReplace any defective components found during testing, such as the solenoid, damaged wiring, or connectors. If the control module is faulty, repair or replace it accordingly.Replacement Solenoid, Wiring Repair Kit
Clear the Code and Test DriveAfter making the necessary repairs, use an OBD-II scanner to clear the P2738 code. Conduct a test drive to ensure that the issue has been resolved and proper transmission function is restored.OBD-II Scanner
Recheck for CodesPerform a final scan after the test drive to confirm that the P2738 code has not returned. If it reappears, further diagnosis may be required.OBD-II Scanner
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Founder of iamcarhacker.com
Hey, I’m Yuri, founder of Iamcarhacker.com. After getting tired of mechanics who either overcharged me or made things worse, I decided to learn everything about car electronics myself. Now I review OBD2 scanners, diagnostic tools, and teach car owners how to fix issues, program new features, and service their cars the smart way.

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