- Joined
- Jan 8, 2021
- Messages
- 36
- Points
- 61
Hello,
I have a 126 with the 1.1 SPI from the Sei.
It has all the wiring loom, ECU, white engine relay etc from the donor car. The white relay I mean is the ECU, injector and fuel pump supply.
For a long time, the whole of the engine was wired to ignition live. This meant that the ECU would lose its learned modifications every time it was switched off, it was effectively being disconnected from the battery each time the ignition was switched off.
I have a bit of time on my hands now and have just changed the wiring to have the white engine relay be supplied with permanent live.
So far, so good. When the ignition is switched off, the relay keeps the power to the ECU (ECU pin 4 sinks current to allow the white relay to energise and supply pin 35 of the ECU from permanent live)....
For about 15 seconds only, after turning the ignition off. The relay then clicks over and power to the ECU is lost.
My question is, what would you expect this relay behaviour to be like typically? Should it permanently supply 12 V to the ECU when the ignition is off?
Or another question, how does the ECU keep power to keep its settings?
The car drives fine enough, but as you can imagine it's probably not optimal considering its doing it's factory learning on my drive to work every day!
I have a 126 with the 1.1 SPI from the Sei.
It has all the wiring loom, ECU, white engine relay etc from the donor car. The white relay I mean is the ECU, injector and fuel pump supply.
For a long time, the whole of the engine was wired to ignition live. This meant that the ECU would lose its learned modifications every time it was switched off, it was effectively being disconnected from the battery each time the ignition was switched off.
I have a bit of time on my hands now and have just changed the wiring to have the white engine relay be supplied with permanent live.
So far, so good. When the ignition is switched off, the relay keeps the power to the ECU (ECU pin 4 sinks current to allow the white relay to energise and supply pin 35 of the ECU from permanent live)....
For about 15 seconds only, after turning the ignition off. The relay then clicks over and power to the ECU is lost.
My question is, what would you expect this relay behaviour to be like typically? Should it permanently supply 12 V to the ECU when the ignition is off?
Or another question, how does the ECU keep power to keep its settings?
The car drives fine enough, but as you can imagine it's probably not optimal considering its doing it's factory learning on my drive to work every day!