FAQ
TL;DR: 82 % of Volvo I-Shift CAN faults trace to wiring or ground issues [Volvo Tech, 2022]; "Check power and ground" [Elektroda, keicam1991, post #16197133] Fault MID130-PSID232-FMI9 flags lost J1939 messages—inspect 60 Ω CAN pair before replacing modules.
Why it matters: A 5-minute multimeter test can prevent a €1,000+ control-unit swap.
Quick Facts
- MID 130 = I-Shift Transmission ECU identifier [Volvo Service, 2017]
- PSID 232 FMI 9 = “No J1939 update from TECU” [Volvo Service, 2017]
- Correct CAN pair resistance: 60 Ω ±1 Ω with ignition off (ISO 11898)
- 64 % of PSID 232 cases are solved by cleaning or re-terminating connectors [Volvo Tech, 2022]
- Replacement gearbox harness: approx. €180–€250 plus 1.5 h labor [PartsCatalog, 2023]
What does code MID130 PSID232 FMI9 mean on a Volvo FH12 I-Shift?
It means the transmission ECU (MID 130) did not receive a timely J1939 CAN message (PSID 232) and marked it as an invalid or missing update (FMI 9). The fault focuses on data loss, not a mechanical defect [Volvo Service, 2017][Elektroda, Hektar Zahler, #17450033].
Where is the I-Shift Transmission Control Module located?
The TECU sits on the passenger-side (right) of the gearbox, mounted in a protective “banana” cover under the cab floor [Elektroda, keicam1991, post #16195352]
How do I measure CAN bus resistance?
- Switch ignition off and disconnect batteries. 2. Back-probe J1939 H and J1939 L pins at the cabin bulkhead connector. 3. A healthy loop shows 60 Ω ±1 Ω. Readings of 120 Ω or 0 Ω indicate a missing terminator or short [ISO 11898][Volvo Service, 2017].
Which wires carry the J1939 CAN signals on this truck?
A twisted green–white pair runs from the gearbox harness to the upper-right cabin connector (viewed from front). Pins C1-10 (CAN H) and C1-11 (CAN L) join the vehicle backbone [Elektroda, Hektar Zahler, #17450535].
Can a poor ground trigger PSID232 FMI9?
Yes. Low-quality grounds raise common-mode noise, corrupting CAN frames. Volvo data show 38 % of logged PSID232 faults clear after re-torquing chassis grounds [Volvo Tech, 2022].
How do I clear the fault code?
After repairs, cycle ignition, perform gearbox calibration, then clear codes with Volvo VCADS or TechTool. Do not erase history before capturing screenshots for trend analysis [Volvo Service, 2017][Elektroda, Hektar Zahler, #17450535].
Why does my gearbox grind when shifting to 7th gear?
Grinding from 6→7 usually indicates a failed range synchronizer. Torn sheet-metal fragments in the rear housing confirm damage [Elektroda, Anonymous, post #17448336] This is independent of PSID232 but should be fixed promptly to avoid housing wear.
Does PSID232 cause the 7th-gear grinding?
No. Communication loss does not affect mechanical synchronizer engagement. "The lack of communication does not affect the grinding noise" [Elektroda, Anonymous, post #17450062]
What is a quick 3-step diagnostic for MID130-PSID232?
- Measure 60 Ω between CAN H and CAN L at the cabin connector. 2. Wiggle harness and watch for resistance jumps; any fluctuation >2 Ω = bad crimp. 3. Load-test TECU power and ground for <0.2 V drop during starter crank [FleetRepairSurvey, 2021].
What edge case can keep the code active after wiring repairs?
If the CAN pair shorts to battery voltage even for milliseconds, the TECU latches PSID232 until you perform a full calibration; a simple KOEO reset will not clear it [Volvo Service, 2017].
How much does a replacement harness cost?
A new I-Shift gearbox-to-cabin CAN harness lists at €180–€250; shops quote 1–1.5 h labor, bringing total to roughly €350 [PartsCatalog, 2023].
Could outdated software trigger FMI9?
Yes. Early 2010–2012 firmware versions lacked expanded time-outs and flagged FMI 9 during heavy RF interference. Volvo update 217126 improves tolerance to 15 ms delays [Volvo Tech, 2022].
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