Estima glow plug control / no pre glow or light but after glow still working? CXR20 3G-TE

[RubberRooster]

HI I am new to this site, I have a neighbor's CXR20 3G-TE Estima to look at and wondering if any one can help. he noticed that his glow plug light no longer came on when he started the vehicle. I replaced the bulb with a new (and tested) globe and then set about trying to find a glow plug timer to no avail. when testing power at the glow plug relay a test lamp across the control wires would light up for a split second when the key was first the key was turned on (ignition) then come back on when the vehicle was started (afterglow) when on the multimeter voltage went to Battery level when ignition turned on for slit second but faded out rather than just off. Checked flash codes for ECU and oddly got code for airflow meter which I didn't think this model Diesel has?

So my questions are does anyone know if the glow plugs are controlled via the main engine ECU or should there be a glow plug timer under the dash some where?

Does it have an airflow meter?

Has anyone had a similar issue?

Anyone have any ideas on fix?

Thank you for taking the time to read my query.