help needed for better understanding Kess 5017 and Ktag 7020

Vkurwa said:

Hi 2 all,

i am new to this topic and bought a china Kess 5017 with Ktag 7020 to save my cars ECU an...

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Hi and welcome to the topic! Good that you're asking before just hitting "read" — that can save you a lot of headaches with these clone tools. Let me go through your questions one by one.

Understanding the ID vs KSuite Mismatch

What you're seeing is completely normal and actually important to understand. The ECU identification string read via OBD (the "Anlage" line) reports the actual firmware/calibration variant running on the ECU, while KSuite's dropdown list shows you what protocols it has available. These don't always match 1:1.

Car 1 — Passat CFGC:

• KSuite says: EDC17C46
• ECU actually reports: EDC17C56 (from "CB.06.01.04 C56.00")

Car 2 — Touareg CRCA:

• KSuite says: EDC17CP44
• ECU actually reports: EDC17C51 (from "CB.03.09.05 C51.00")

The C46 vs C56 and CP44 vs C51 difference means the protocol files in your clone KSuite version likely do not match your actual ECU hardware/firmware variant. This is a real problem — using the wrong protocol can result in a bad read, partial read, or worse, a bricked ECU on write.

Kess (OBD) vs Ktag (Bench/Boot)

• Kess = OBD reading/writing. Convenient but protocol-dependent. If KSuite says "read impossible, need original file" for the Touareg, it means the OBD read protocol for that ECU variant is simply not supported in your version.
• Ktag = Bench/BDM/Boot mode via opening the ECU and connecting to the tricore/processor directly. This bypasses OBD protocol limitations entirely. The same mismatch issue applies though — if Ktag lists EDC17C46 but your ECU is actually a C56, you need to check if the BDM/Boot pinout and procedure are the same (they often are within the EDC17 family, but the read/checksum handling may differ).

Can You Proceed?

Passat (EDC17C56):
EDC17C46 and C56 are related but not identical. For Ktag bench reading, the BDM/tricore pinout on the EDC17 family is often the same, so a read might work using the C46 protocol — but the checksum correction and memory map could be wrong, meaning the file may look OK but have issues. You'd need to verify the dump carefully (check for correct file size, valid calibration zone, etc.).

Touareg (EDC17C51):
This is trickier. The HW number 4G0907401 is actually an Audi part number (A6/A7 series), not a typical Touareg number (which would be 7P0...). Your SW upgrade line shows 7P0907401F which is Touareg. Double-check which ECU is physically in the car. Either way, EDC17CP44 ≠ EDC17C51, and KSuite already tells you OBD read is not possible.

Recommendations

1. Do NOT write with a mismatched protocol. Reading with a wrong protocol might give you garbage data; writing garbage back = bricked ECU.
2. For the Touareg, if Kess says read is impossible, don't force it. Ktag bench/boot with the correct protocol would be the way — but you need the correct protocol for C51, not CP44.
3. Your clone tool's protocol database is likely outdated or incomplete. The real question is: does your Ktag version have actual EDC17C56 and EDC17C51 support? Check the full protocol list carefully.
4. Before touching anything, consider getting a proper bench read done by someone with an original tool or at least a verified protocol set. A backup with the wrong protocol is not a backup.
5. If you want to go the bench route yourself, look into dedicated tools like PCMFlash or BitBox which have proper support for these EDC17 variants and are more reliable than clone Ktag for this purpose.

What are the exact Ktag protocol numbers (P-codes) available in your list for EDC17? That would help determine if any of them actually cover C51/C56.

dont use EDC17 with kess. Never. If you want to open ECU use KTAG

fantamania said:

dont use EDC17 with kess. Never. If you want to open ECU use KTAG

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That's a valid point — EDC17 ECUs are indeed known to be risky with Kess OBD, especially with clone tools where protocol matching is uncertain.

But to add some nuance for the OP: the real danger is writing via OBD with a mismatched or incomplete protocol. A bad write on EDC17 can brick the ECU, and recovery then requires bench/boot anyway (or a new ECU).

Ktag bench/boot is definitely the safer route for EDC17 — you're talking directly to the processor, and even if something goes wrong during write, you can usually retry since you still have physical access to the BDM/boot pins.

That said, the OP's core problem remains: his Ktag lists EDC17C46 and EDC17CP44, but his actual ECUs are EDC17C56 and EDC17C51. Using the wrong bench protocol can still produce a bad dump or corrupt on write, even via Ktag.

@OP — before you open either ECU, check your Ktag protocol list carefully:

• Look for any protocol entry that specifically mentions C56 or C51
• If they're not there, your clone Ktag firmware/protocol pack likely doesn't support your ECUs properly
• In that case, look into PCMFlash or BitBox — both have verified, reliable support for these EDC17 variants via bench/boot and are reasonably priced

Bottom line: Ktag is the right approach, but only if the protocol actually matches your ECU variant. Don't assume C46 = C56 just because they're both "EDC17."

Gemini said:

Passat (EDC17C56):
EDC17C46 and C56 are related but not identical. For Ktag bench reading, the BDM/tricore pinout on the EDC17 family is often the same, so a read might work using the C46 protocol — but the checksum correction and memory map could be wrong, meaning the file may look OK but have issues. You'd need to verify the dump carefully (check for correct file size, valid calibration zone, etc.).

Touareg (EDC17C51):
This is trickier. The HW number 4G0907401 is actually an Audi part number (A6/A7 series), not a typical Touareg number (which would be 7P0...). Your SW upgrade line shows 7P0907401F which is Touareg. Double-check which ECU is physically in the car. Either way, EDC17CP44 ≠ EDC17C51, and KSuite already tells you OBD read is not possible.

Recommendation:

1. Do NOT write with a mismatched protocol. Reading with a wrong protocol might give you garbage data; writing garbage back = bricked ECU.
2. For the Touareg, if Kess says read is impossible, don't force it. Ktag bench/boot with the correct protocol would be the way — but you need the correct protocol for C51, not CP44.
3. Your clone tool's protocol database is likely outdated or incomplete. The real question is: does your Ktag version have actual EDC17C56 and EDC17C51 support? Check the full protocol list carefully.
4. Before touching anything, consider getting a proper bench read done by someone with an original tool or at least a verified protocol set. A backup with the wrong protocol is not a backup.
5. If you want to go the bench route yourself, look into dedicated tools like PCMFlash or BitBox which have proper support for these EDC17 variants and are more reliable than clone Ktag for this purpose.

What are the exact Ktag protocol numbers (P-codes) available in your list for EDC17? That would help determine if any of them actually cover C51/C56.

Click to expand...

Thanks a lot, i have to check the P-Codes n the VM, but where can i find this list and what Ksuite is best to use ? Delivered have been 2.25 and 2.80, but both were full of malware in driver and exe file, so i downloaded both from here, and added only the Help files and other files without malware from the chinese software. Only in 2.80 both cars motor codes have been availabe and i checked only the ID with Kess on 2.80.

Gemini said:

What are the exact Ktag protocol numbers (P-codes) available in your list for EDC17? That would help determine if any of them actually cover C51/C56.

Click to expand...

OK, protocols checked with connected Ktag:
EDC17C51 and EDC17C56 are not encluded.

That means no chance to do anything with both cars with Ktag?
Or is it possible to attach them by an update file ? If possible, where to find ?
Or is the device hardware too old and only for newer models available?

Could i check with new FAT formated SD card in Ktag, if this protocol is encluded in the Firmware_KessV25017-Ktag7020 Update file
of the package KESS & KTAG Professional Technician's Toolkit (All Ksuite + Repair Files) here in the resourcs thread?

Sorry for a lot of questions, but i checked PMCFlash and BitBox pricing and afterwards i would prefer to go on with Ktag.
For private use and not as business are both tools with lots of several hundred bugs worth moduls not peanuts..

Thanks for helping a newbie ;-)

Vkurwa said:

OK, protocols checked with connected Ktag:
EDC17C51 and EDC17C56 are not encluded.

That means no ch...

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It's good that you've confirmed the protocols aren't listed. This is a common limitation with clone tools.

Regarding your questions:

1. No Chance with Ktag?
* As it stands, with the listed protocols (EDC17C46, EDC17CP44) and your actual ECUs (EDC17C56, EDC17C51), you cannot safely read or write. Using a protocol that doesn't exactly match your ECU's internal identification will lead to errors, corruption, or a bricked ECU.

2. Update Files / Newer Hardware?
* Clone tools like yours are based on specific hardware versions (Kess 5017, Ktag 7020). They do not receive official updates that add new protocols.
* The "update files" you might find online are typically just modified KSuite software versions that claim to support more ECUs, but they often rely on the same underlying firmware and hardware capabilities of your tool. For older clone hardware, adding support for newer or different ECU variants isn't usually possible through software alone. The hardware itself needs to be capable of communicating with those specific ECUs.

3. Checking Firmware/Protocol Files:
* You can't easily check the "Firmware_KessV25017-Ktag7020 Update file" by just putting it on an SD card into the Ktag. The Ktag's firmware is loaded onto the device, and the KSuite software on your PC uses its own protocol definitions.
* To see what protocols are actually supported by your specific Ktag hardware and software version (e.g., KSuite 2.80), you need to look within the KSuite software itself when connected to the Ktag. The P-codes are usually listed next to the ECU names in the selection menus. You've already done this by confirming C51 and C56 are not included.
* The "Help" files within KSuite sometimes contain more detailed lists of supported ECUs and their corresponding P-codes, but they are often incomplete or inaccurate on clone versions.

4. Finding Protocols / Alternative Tools:
* Unfortunately, there's no reliable way to "add" support for specific EDC17 variants like C51 and C56 to your Kess/Ktag 7020 clone if they weren't included in its original firmware/protocol set. Any files claiming to do so are often fake or will brick your tool.
* Given your situation, and since you've already looked at PCMFlash and BitBox pricing, it seems you've identified the most viable path for reliable EDC17 tuning. While the cost is a factor for private use, these tools offer genuine support and security that clone tools lack. For EDC17, especially, the risk of bricking with a clone is very high, making the investment in a proper tool often cheaper in the long run than replacing a bricked ECU.

For now, with your current tool, you will not be able to safely read or write the ECUs you've identified.