Understanding the Chery Ev TPMS System
The Chery Ev uses a direct TPMS system, meaning each wheel has a physical sensor inside the tire that transmits pressure and temperature data to the vehicle’s ECU. The system operates at 433MHz, which is standard for many Chinese-manufactured EVs and shared with other Chery group vehicles like Cowin and Exeed.
If you are replacing a faulty sensor or installing a new set, the BL-ST-038 is a pre-programmed clamp-in sensor that matches the original equipment from Baolong Technology (BH-Sens). It covers OE numbers 802000121AA, 802000126AA, and F02361701001AA. Because it is pre-programmed, you do not need a separate programming tool—it will sync with the vehicle after installation and a short drive.
Installation Torque Specs: What the Manual Tells You
Chery does not publish a universal torque value for all models, but the standard for M6 valve stem nuts on clamp-in TPMS sensors is 35–40 in-lbs (4–4.5 Nm) . This applies to the Chery Ev.
Critical: Do not torque the sensor to the wheel. The torque spec applies only to the hex nut that secures the valve stem to the wheel rim. The sensor body itself must not be used as a leverage point.
| Component | Torque Range | Tool | Notes |
|---|---|---|---|
| Valve stem hex nut | 35–40 in-lbs (4–4.5 Nm) | Torque wrench (inch-pounds) | Use a crow’s foot adapter if clearance is tight |
| Sensor mounting screw | Hand-tight + ¼ turn | Small flathead or T10 Torx | Never use power tools |
| Tire valve cap | Hand-tight | Fingers | Over-tightening damages the sealing o-ring |
If you do not have an inch-pound torque wrench, err on the side of lower torque. A common mistake is tightening the nut by feel until it “stops,” which often exceeds 60 in-lbs and cracks the sensor housing.
Valve Stem Service: Replace the Sealing Components
Every time a TPMS sensor is removed from a wheel, the sealing grommet (rubber washer) and the metal washer must be replaced. The old grommet compresses permanently and will leak if reused.
Step-by-step for the Chery Ev:
- Remove the tire from the rim using a tire machine. Manual tire irons can damage the sensor.
- Clean the valve stem hole in the rim with a wire brush or drill-mounted nylon brush. Remove all old rubber residue and corrosion.
- Install a new rubber grommet onto the valve stem, followed by the metal washer. The metal washer goes on top of the grommet (closest to the nut).
- Insert the sensor through the rim hole. Push the valve stem through until the grommet sits flush against the rim.
- Thread the hex nut by hand, then torque to 35–40 in-lbs.
- Mount the tire, inflate to the sticker pressure (usually 36–38 psi for the Chery Ev), and check for leaks with soapy water.
Never apply threadlocker or grease to the valve stem nut. The nut is designed to lock with friction and a dry thread. Lubricants can cause the nut to loosen over time.
Common Installation Mistakes (and How to Avoid Them)
1. Over-torquing the Sensor Nut
This is the #1 killer of clamp-in sensors. When the nut is tightened beyond 40 in-lbs, the plastic sensor housing deforms, the internal battery connection breaks, or the valve stem cracks. The sensor may still transmit for a few days, then fail completely.
Fix: Use a torque wrench set to inch-pounds, not foot-pounds. If you hear a “pop” or feel the nut suddenly turn easier, you have stripped the threads—replace the sensor.
2. Installing the Grommet Backwards
The rubber grommet has a beveled edge on one side. That bevel must face the rim. If installed backwards, the grommet will not seal, and you will have a slow leak.
Fix: Look at the old grommet before removing it. The beveled side always contacts the rim. The flat side faces the metal washer.
3. Using the Wrong Sensor for the Rim Type
The Chery Ev uses a standard clamp-in sensor. Do not use a “snap-in” rubber valve stem sensor—those are designed for steel wheels and will not seal properly in the Chery’s aluminum rim.
4. Not Relearning the Sensor After Installation
The BL-ST-038 is pre-programmed, but the car’s ECU still needs to learn the sensor’s ID. After installation, drive the vehicle at speeds above 15 mph for 5–10 minutes. The system will auto-learn the new sensor. If the TPMS light stays on, use a TPMS tool to trigger the sensor manually.
5. Cross-Threading the Valve Stem Nut
Aluminum rims are soft. If you start the nut crooked, you will damage the threads on the valve stem or the rim hole.
Fix: Always start the nut by hand. Spin it until you feel the threads engage smoothly. Only then use a wrench.
Recommended Part
If you are replacing a failed sensor on your Chery Ev, the BL-ST-038 | BH-Sens 433MHz TPMS Tire Pressure Sensor | Fits Chery, Chery Ev, Cowin, Exeed | OE# 802000121AA, 802000126AA, F02361701001AA is a direct-fit, pre-programmed option. It comes with the correct grommet and washer kit. No programming tool is required for most Chery Ev models—just install, drive, and the light should go out.
FAQ
Can I install the BL-ST-038 sensor myself without a tire machine?
No. You need a tire machine to avoid damaging the sensor during tire removal and installation. Attempting to spoon a tire off manually can crush the sensor housing. A tire shop will typically charge $20–$40 per wheel for mount and balance.
How long does the battery last in the BL-ST-038?
Baolong sensors typically have a battery life of 5–7 years. The BL-ST-038 is sealed and cannot be repaired—replace the entire sensor when the battery dies. The sensor will usually give a low-battery warning on the dash before it stops transmitting.
The TPMS light is still on after driving. What do I do?
First, check tire pressures with a gauge. If all tires are at the correct pressure, drive an additional 10 minutes at highway speeds. If the light remains on, a TPMS trigger tool (like an Autel or Bartec) may be needed to wake the sensor. Some Chery Ev models require a relearn procedure using the car’s menu system—consult your owner’s manual.
Does the BL-ST-038 fit other Chery models besides the Ev?
Yes. It fits Chery, Cowin, and Exeed vehicles that use the same 433MHz system. Check the OE numbers on your current sensor: if it is 802000121AA, 802000126AA, or F02361701001AA, the BL-ST-038 is a direct replacement.