FAQ
TL;DR: 78 % of Opel Astra H CIM faults trace to the 9S12DG128 or 93xx EEPROMs; “read the MCU directly, not via CAN” [Elektroda, MikeC, post #17260967] Xprog-M 5.55+ dumps both flash and eeprom in ≤3 min. Use a PIN calculator if the dump looks blank.
Why it matters: Correct identification and reading prevent steering-sensor, key, and VIN mismatches.
Quick Facts
• MC9S12DG128: 128 kB flash, 4 kB EEPROM, BDM @ 5 MHz [NXP RefMan].
• 93LC76/95160 SOIC-8: 8–16 kbit, 2.5-5.5 V supply [Microchip DS20001749].
• Used CIM price: €40–€120 (EU dismantlers, 2023 listings).
• Time-lock after wrong PIN: 10 → 80 min exponential back-off [GM TIS2000].
• Rear-wiper function absent on sedan CIM PCB variant [Elektroda, stalin2, post #20341428]
1. How do I identify the small ICs marked 6250G and AUS5790D?
Both codes belong to 93LC76-compatible serial EEPROMs (8 kbit, SOIC-8). They replace 95160 in late Astra H CIMs [Elektroda, grzegorz__1976, post #17260687] Pin-1 indicator and SOIC-8 footprint confirm the part.
2. Which memory actually holds the car’s PIN code?
The four-digit immobiliser PIN sits in the internal EEPROM of the MC9S12DG128 MCU, not in the external 93xx chip [Elektroda, tomek4, post #18958794]
3. Best way to read a 9S12DG128 dump?
Use Xprog-M v5.55 or newer with BDM cable, 12 V external, and ‘MC9S12DG128-Sec’ template. Average read time is 2–3 minutes [Elektroda, lukasz12345678910, post #20190133]
4. Why does Xprog show an empty EEPROM?
Most ‘blank’ dumps result from reading only the flash sector. Select “Full-mem + EEPROM”; otherwise file size is 0x20000 without the 0x1000 EEPROM area [Elektroda, lukasz12345678910, post #17293692]
5. How long must I wait after entering a wrong PIN?
GM firmware applies exponential back-off: 10, 20, 40, then 80 minutes. Disconnecting battery resets nothing [GM TIS2000].
6. Can CIM 13313710 ML be swapped for a model using 93C86?
No. The 93C86 CIMs use different PCB and steering-angle logic. Swap only same hardware revision or you lose ESP calibration [Elektroda, lukasz12345678910, post #17293692]
7. Does copying the external EEPROM make two CIMs plug-and-play?
Only if the PCB, MCU mask, and firmware match exactly. Otherwise VIN, PIN, and variant coding stay in the MCU memory and the car will not start [Elektroda, kamyczek, post #20365110]
8. Quick 3-step: extracting the PIN code
- Read full flash + EEPROM with Xprog.
- Load BIN into ‘CIM PIN Calculator’ (Hamster release).
- Note four-digit output and test with Tech2/Op-Com. Success rate ≈92 % on first try [Hamster README].
9. Edge-case: “High error boot” when reading – fix?
The MCU sets a security byte after brown-out events. Power the board from lab supply at 13.8 V and ground RESET; retry read. 1 in 20 units still fail and need J-Link erase [Elektroda, grzegorz__1976, post #17295787]
10. Why does the rear wiper option disappear on sedan CIMs?
Sedan CIM PCBs omit the two lever contacts; firmware also hides wagon features. Swapping only the stalks will not restore the output [Elektroda, stalin2, post #20341428]
11. Can I recover the mechanical key cut from a CIM dump?
No. The CIM stores transponder crypto only, not the physical blade code. You need VIN-to-key service from Opel EPC [Elektroda, ziempiotr, post #18960788]
12. How do I unlock steering-angle sensor calibration?
Enter correct PIN, turn wheels ±15°, then steer to zero and run ‘SAS Calibrate’ in Op-Com. Takes <2 minutes when CIM accepts the PIN [Elektroda, ic3ek, post #18976559]
13. What does a blank VIN in CIM coding indicate?
It means the module is virgin or was reset; the car will crank but not start until coded with Tech2 using the correct PIN [Elektroda, lukasz12345678910, post #17295749]
14. Typical replacement cost and labour time?
Used CIM €80 median, 0.9 h labour for swap and coding per GM flat-rate manual [Opel Labour Guide, 2022].
