Hi is it a Diode or Resister between pins 85-86 on the 53 relay

 

It's a resistor. Some other generic SPST and SPDT Bosch style relays have a reverse biased diode across the coil (reverse biased as long as 86 is more positive than 85 - which it should be). These are both snubbers for the relay coil's inductive switching pulse, the resistor shunts it mildly in both directions, while the diode shunts it harder but only negatively. The resistor dissipates some additional operating power - while the diode does not.

Alan