Renault Trucks / ZF AS-Tronic Codes: SPN 21, 22, 82, 93, 117, 118 and 163
Updated: 2026-11-13
What these codes are
SPN 21, 22, 82, 93, 117, 118 and 163 appear in Renault Trucks and ZF AS-Tronic diagnostics. In the factory wording they all point to the automated gearbox control side of the truck: the clutch actuator and its wiring, the clutch position sensor, the signal between the transmission control unit and the engine, or the control unit itself. Each code appears with a single FMI, and each carries one Renault Trucks line.
One thing to know before you start: the J1939 name for the SPN and the Renault Trucks wording do not describe the same component. For example, SPN 117 is listed in the J1939 table as Brake Circuit #1 Pressure, while Renault Trucks words it as a clutch initialisation error. The table below shows both, so you can match the code on your scanner to the right line. This is about the Renault Trucks and ZF AS-Tronic reading of the code; the J1939 name may not be the system your fault is in.
SPN, wording and FMI
| SPN | J1939 name | FMI | Renault Trucks / ZF AS-Tronic wording |
|---|---|---|---|
| 21 | Engine ECU Temperature | 5 | Short to 0 V. Check the wiring between the control unit and the clutch actuator; run the diagnostic check of the clutch actuator. |
| 22 | Crankcase Pressure (Extended Range) | 5 | Clutch and lever angle position sensor, short to 0 V. Same wiring and actuator checks as SPN 21. |
| 82 | Engine Air Start Pressure | 6 | Short to battery positive. Check the wiring between the control unit and the clutch actuator (X1B/12, X1B/16); run the diagnostic check of the clutch actuator. |
| 93 | Engine Net Brake Torque | 8 | ASR engine signal fault. Run the diagnostic check of the EBS unit and check the programming. |
| 117 | Brake Circuit #1 Pressure | 0 | Clutch initialisation error. Run the diagnostic check of the clutch actuator and check the wiring to the control unit. |
| 118 | Brake Circuit #2 Pressure | 0 | Clutch fault. Same checks as SPN 117. |
| 163 | Transmission Current Range | 0 | Engine does not respond to transmission control. Use the engine communication diagnostic check, run the diagnostic check of the EECU and check the programming. |
What the FMI means
| Code | J1939 meaning of the FMI | Renault Trucks wording |
|---|---|---|
| SPN 21 and 22, FMI 5 | Current below normal or open circuit | Short to 0 V |
| SPN 82, FMI 6 | Current above normal or grounded circuit | Short to battery positive |
| SPN 93, FMI 8 | Abnormal frequency or pulse width | ASR engine signal fault |
| SPN 117, 118 and 163, FMI 0 | Data above normal range (most severe level) | Clutch initialisation error, clutch fault, engine not responding to transmission control |
Note that for SPN 21, 22 and 82 the standard FMI meaning and the Renault Trucks wording read differently (open circuit against short to 0 V; grounded circuit against short to battery positive). Quote the wording that matches your tool, and do not assume one cancels the other.
Checks that apply to all seven codes
- Switch the ignition off, switch it on again and repeat the test. See whether the same code returns.
- For the clutch-related lines (SPN 21, 22, 82, 117, 118), run the diagnostic check of the clutch actuator and check the wiring between the control unit and the clutch actuator. For SPN 82 the Renault Trucks line names the pins X1B/12 and X1B/16.
- For SPN 93, run the diagnostic check of the EBS unit and check the programming.
- For SPN 163, use the engine communication diagnostic check, run the diagnostic check of the EECU and check the programming.
- If the fault persists after these steps, the Renault Trucks lines end with replacing the control unit. It comes last.
Can I keep driving?
The verdict differs by code, so it is given per code. For every one of them, let the air system build to working pressure and listen for leaks; do not drive with faulty brakes.
- SPN 82, 93, 117, 118: do not drive. Stop as soon as it is safe; the time you have is minutes. Part of the brake circuit or ABS/EBS is out of service, the pedal may still feel normal until the first emergency stop or descent, and next come a longer stopping distance, a skid on a slick surface or failure on a long downgrade. "I will take it slow" does not work here.
- SPN 21 and 22: drivable, but watch it yourself. This is an electrical fault: an open, a short or a bad contact in the circuit, and the value it measures is most likely fine. You can drive, but until the circuit is repaired this system runs blind and cannot warn you about a real failure.
- SPN 163: safe to drive to the nearest safe stop. The gearbox or clutch has gone into limp mode: some gears may be unavailable and an automated box may stop shifting under load. The main risk is being left on a climb with no gear and rolling back. Do not take a loaded truck into the hills; reaching level ground and a shop is fine.
FAQ
Is SPN 117 a brake pressure fault or a clutch fault?
The J1939 name of SPN 117 is Brake Circuit #1 Pressure, but the Renault Trucks wording is a clutch initialisation error. SPN 118 is listed as Brake Circuit #2 Pressure, with Renault Trucks wording of a clutch fault. Use the wording that matches your tool and the make of your truck.
What is the difference between SPN 117 and SPN 118?
Both are FMI 0 with the same checks. The Renault Trucks line for 117 is a clutch initialisation error and for 118 a clutch fault.
What do I check first for SPN 82, 21 or 22?
The wiring between the control unit and the clutch actuator, then the diagnostic check of the clutch actuator. For SPN 82 the Renault Trucks line names the pins X1B/12 and X1B/16.
What does SPN 163 mean for driving?
The gearbox or clutch is in limp mode. Some gears may be missing and an automated box may stop shifting under load, so avoid hills with a loaded truck and go to a shop.
When do I replace the control unit?
Last. The Renault Trucks lines say to switch the ignition off and on, repeat the test, and replace the control unit only if the fault persists.
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