Operating Voltage

[mrsr32]

Hi

I've just installed an Apexi RSM, this uses the ign power wire from the ecu as its source.

The voltage reported on the RSM with the fan on 1 and headlights on, can drop down to around 12.4v and at idle around 11.8v.

Is my alternator on the way out? What should the operating voltage be? around 13.8v?

Going to get the multimeter out to check voltage at the battery tonight.

[Duncan]

Either alternator, battery or just wiring to the RSM (including bad earth, dont just thing about positive side). Yes around 14v depending on how cold the car is, and yes a multimeter at the battery when stopped (~12v) and running (~14v) is the next step

[jiffo]

Check fan belt tension too, takes a fair hp to pull an alternator under max load.

[mrsr32]

Voltage was the same as the battery when running around 12.8. Battery was 12.3 when cold

[Duncan]

then you have some sort of battery earth or alternator issue, an auto elec can test and repair the alternator

[mrsr32]

Thanks!

[junkie]

12.6v for a healthy fully charged battery. should see between 13.5v and 14.5v when engine is idling and lights off, with most nissans producing around 14.1v at idle