Fuel gage/Cluster fuel needle question

[Futaba]

Hi all,
Would anybody happen to know what sort of signal range is expected from the fuel sender+gage to pins 27 and 28 on the cluster? Such as voltages etc.

Thanks

[RedReplicant]

I posted about this in the KSwap FB group. Keep in mind level on the cluster is also based on fuel quantity injected coming from the ECU over CAN, but here is what I wrote:

There are two fuel sending units, each have different ranges in the service manual. fuel pump side is 6.5-8.5 ohms for full and 168-172 ohms for empty, other side is 5.5-9.5 ohms for full and 236-244 ohms for empty. The diagram indicates the fuel level sensor wires at the cluster just run through these two sensors sequentually, so add the resistances of the two together. I haven't tested this on an IC7, but it seems like full would be under 18 ohms and empty would be over 404 ohms.

If using AVI4 on Haltech IC7 with 240 ohm pull up then .34v full, 3.13v empty. If using other AVIs on Haltech IC7 with 1k ohm pull up then .08v full, 1.44v empty. Recommend using AVI4, adding known amounts of fuel at a time, measuring the resistance and building a table on your own.