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BQ24041: (BQ24040) circuit doesn't charge, but why?

Part Number: BQ24040
Other Parts Discussed in Thread: BQ24041

I've used the BQ24041 with success on previous designs.  However, I have a new board that does not charge the battery.  The battery is LIP 3.7V 500mAh.  I connected the battery to a different design using the BQ24041 and it charges fine.  The battery is good.

I attached a capture of the batt charger circuit.  V1 is usb vbus (5V).

In previous designs, I used Iset to program a higher fast charge current.  For this design 500mA was sufficient, so I left Iset disconnected and tied Iset2 high.

While the battery charges, there is no other parallel load.  The data sheet says pre_term can be left floating to program default values of 10% and 20% for pre-charge and termination.  Space is very tight so that's what I did.

My interpretation of the datasheet was that Iset2 would supersede Iset.  Is the program resistor for Iset actually necessary regardless?

The board is small and the components are tightly packed.  The resistors are 0402 so i don't have many options to modify the circuit.  My next step is to configure a working board with the same circuit to see if it works.

Any ideas what may be the problem?