What Does P099D Mean?
The TCM has detected that shift solenoid 'H' is not performing within its expected range. The solenoid's response does not correlate with commanded duty cycle, indicating a mechanical or hydraulic performance issue. Solenoid H is used in advanced multi-speed transmissions (8+ speeds) for controlling additional clutch packs or torque converter control.
Common Causes
35%
Shift solenoid H sticking or sluggish from contaminated transmission fluid
25%
Valve body passages for solenoid H circuit restricted or worn
20%
Resistance fault in solenoid H wiring causing improper current delivery
20%
Solenoid seal failure causing hydraulic pressure bleed-off
Diagnostic Steps
1
Step 1: Inspect transmission fluid level and condition. Perform a fluid analysis if possible to check for clutch material, metal, and varnish contamination.
2
Step 2: Use live data to monitor solenoid H commanded vs. actual duty cycle during driving. Identify which gear transitions exhibit the fault.
3
Step 3: Measure solenoid H resistance at the transmission case connector. Compare against manufacturer specification (typically 10-25 ohms).
4
Step 4: Remove the transmission pan and inspect for excessive debris. Inspect the solenoid H screen filter for contamination blockage.
5
Step 5: Remove the valve body and inspect solenoid H bore and associated passages. Check for scoring, stuck valves, or missing/displaced check balls.
Estimated Repair Cost
$200 - $900
Parts + labor, varies by vehicle and location
The TCM has detected that shift solenoid 'H' is not performing within its expected range. The solenoid's response does not correlate with commanded duty cycle, indicating a mechanical or hydraulic performance issue. Solenoid H is used in advanced multi-speed transmissions (8+ speeds) for controlling...
The most common cause of P099D (Shift Solenoid "H" Control Circuit Range/Performance) is: Shift solenoid H sticking or sluggish from contaminated transmission fluid
Typical repair costs for P099D range from $200 to $900, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Shift quality degradation in specific gears. Possible flaring, slipping, or harsh engagement. Avoid towing and extended highway driving until repaired.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P099D to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Transmission Shift Control
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
