Update query using IIf() in a WHERE condition

Question

I am writing an update query in Access which is based on a make table query.

In my temporary table (the output of my make table query), I have 3 fields [Tick], [DivLevel4] and [T]. I can have identical Ticks displaying different values for [DivLevel4] if [T] bears different values (only C or F):

Tick    DivLevel4  T

AA      5          C
AA      0          F
BB      2          C
CC      3          C
CC      0          F

How can I incorporate this condition in my update query? I have tried adding an IIf() statement in the criteria field but it is not doing the job:

IIf([tblTrades].[T]="Y",0,[tbl_DIV_Temp].[[DivLevel4])

as in

UPDATE 
    tblTrades 
    INNER JOIN 
    tbl_DIV_Temp 
        ON tblTrades.Tick = tbl_DIV_Temp.Tick 
SET tblTrades.DIV = [tbl_DIV_Temp].[DivLevel4]
WHERE (((tblTrades.DIV)=IIf([tblTrades].[T]="F",0,[tbl_DIV_Temp].[DivLevel4])));

Answer 1

Topic is close. Alternative method found.