Tips to Read Mazda Denso SH72543 ECU with Xhorse Multi Prog:
Try these steps:
1. Power Supply and Voltage Adjustments
External Power: Ensure you are using the original 15V/4A power adapter for the Multi-PROG. If you are relying solely on USB or a weak power source, it will fail when accessing larger data blocks like Maps.
Adjust VDD Voltage: In the software settings, try adjusting the VDD voltage to 4.7V or 4.8V (if it’s at 5V) or slightly increasing it if it’s too low. Sometimes a slightly lower voltage prevents the “overcurrent” trip.
2. Hardware Connectivity
Heat the Chip: A common professional fix for SH-series chips is to use a heat gun to warm the chip to approximately 50°C before starting the read. This often stabilizes communication for the Map area.
Check Pin 24 (CLK): This pin is notorious for poor contact on Denso ECUs. Ensure the connection is rock-solid; even a tiny amount of resistance can cause a timeout during the longer Map reading process.
3. Tool Troubleshooting
Self-Test: Disconnect the ECU and run “Test Channel” in the software to confirm the DB44 cable and internal hardware are outputting the correct 3.3V/5V.
Force Firmware Update: If the issue persists, the protocol might be glitchy. You can force a firmware refresh by holding the Reset button on the unit for 5 seconds while powering it on, then re-updating via the Xhorse software.
4. Alternative Method
Boot Mode vs. Bench: If you are currently in Bench mode, try switching to Boot mode (Tricore BSL) if the diagram is available. Boot mode is generally more stable for full data extraction.