# CLASSIC V3 FIRMWARE - Issues with flexfuel sensor and ignition output **URL:** \ **Category:** EMU CLASSIC V3 BETA\ **Created:** [July 7, 2026, 2:44pm UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153 "2026-07-07T14:44:44Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Gabin](https://avatars.discourse-cdn.com/v4/letter/g/3e96dc/32.png) [@Gabin](https://community.ecumaster.com/u/Gabin)\ **Post date:** [July 7, 2026, 2:44pm UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/1 "2026-07-07T14:44:44Z")
Hello, I recently upgraded my **EMU Classic** to firmware **V3.066** and I am experiencing two issues that were not present with the previous V2 firmware. ### **1. Ignition output used for the coolant fan** I use one of the **unused ignition outputs** to control my coolant fan. Since upgrading to V3.066, the coolant fan turns on **immediately when the ignition is switched on** , even with a cold engine. This configuration worked perfectly before the firmware update. ### **2. Flex Fuel sensor** My **Continental Flex Fuel sensor** is connected to the **CAM2 input**. Since the upgrade: - **FF Status = Disabled** - **FF Sensor Frequency = 0 Hz** - **CAM2 Input Level = Low** - **CAM2 Signal Present = No** - Ethanol content remains fixed at **85%** , even when the sensor is disconnected. - The **Failsafe Ethanol Content** is configured to **12%** , but this value is never applied. I have already verified the following: - Sensor power supply: **12.2 V present** - Sensor ground: **OK** - Continuity between the sensor signal wire and the ECU CAM2 input: **OK** - The same sensor and wiring worked correctly with the previous firmware before the upgrade. Could this be a known issue with firmware **3.066 (still same with 3.067)** , or is there any additional configuration required in V3 for the Flex Fuel input or ignition outputs? If needed, I can provide my **.emu project file** , screenshots of the configuration, and any additional information required. Thank you in advance for your support. ---
**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\ **Post date:** [July 7, 2026, 9:20pm UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/2 "2026-07-07T21:20:37Z")
Could you please publish your base map ? The ignition output used as an output for coolant fan seems to work properly. ---
**Author:** ![Gabin](https://avatars.discourse-cdn.com/v4/letter/g/3e96dc/32.png) [@Gabin](https://community.ecumaster.com/u/Gabin)\ **Post date:** [July 8, 2026, 6:42am UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/3 "2026-07-08T06:42:50Z")
[20260705\_1732\_33\_FIRMWARE\_UPGRADE-CITROEN SAXO TU5JP4.zip](https://community.ecumaster.com/uploads/short-url/wURp6GOExfd9epxakJWg2wGhYWc.zip) (69.7 KB) **Hi,** Here it is! It’s strange. When I was running firmware **1.227** , the coolant fan worked perfectly. After upgrading to **V3** , the coolant fan started running **as soon as the firmware update was completed** and **the ignition was switched on**. ---
**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\ **Post date:** [July 8, 2026, 10:01pm UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/4 "2026-07-08T22:01:50Z")
In V3, the ignition output works opposite to the Classic V1 firmware. It works the same way as in EMU BLACK. When active coils are selected, the output is 12 V when active and ground when inactive. When passive coils are selected, the output is ground when active and floating when inactive. Please enable the **“Invert Output”** checkbox in the coolant fan parameters. ---
**Author:** ![Loch](https://avatars.discourse-cdn.com/v4/letter/l/e68b1a/32.png) [@Loch](https://community.ecumaster.com/u/Loch)\ **Post date:** [July 9, 2026, 1:39am UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/5 "2026-07-09T01:39:00Z")
any fix for the flex fuel issue? im also experiencing the exact same issue, tested with 2 seperate classics ---
**Author:** ![Gabin](https://avatars.discourse-cdn.com/v4/letter/g/3e96dc/32.png) [@Gabin](https://community.ecumaster.com/u/Gabin)\ **Post date:** [July 9, 2026, 9:39am UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/6 "2026-07-09T09:39:49Z")
Ok thank you, I’ll check. What about the FF sensor ? ---
**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\ **Post date:** [July 9, 2026, 10:10am UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/7 "2026-07-09T10:10:49Z")
I’m working on it. I will give you feedback soon ---
**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\ **Post date:** [July 9, 2026, 9:31pm UTC](https://community.ecumaster.com/t/classic-v3-firmware-issues-with-flexfuel-sensor-and-ignition-output/6153/8 "2026-07-09T21:31:25Z")
The FlexFuel support in Classic V3 is broken. It will be fixed in next build. The build is planned in next week.