Author Topic: Can anyone assist in identifying a SMD diode?  (Read 1189 times)

0 Members and 1 Guest are viewing this topic.

Offline poor_red_neck

  • Newbie
  • Posts: 3
Can anyone assist in identifying a SMD diode?
« on: April 23, 2014, 01:33:35 PM »
Hello all,

Novice electronics diagnostician... trying to repair a body control module from my vehicle. Long story short I goofed up and fed battery+ (12V) into the ground side switch of the BCM.

The diode reads open in both directions, so looks like this is my culprit after tracing the PCB traces. Here's what I know:

The markings on the diode are:

A4
V2G   (or V26 can't tell)

In the attached picture, the diode in question is D22 (same as D21-D26)

Can't find my micrometer so don't have a measurement, but approximately 2.5-2.75mm long by 1.0mm wide.
This part of the circuit drives an automotive relay, 95mA draw on the relay. It its ground side switched by a N channel MOSFET. The drain of the MOSFET goes to the anode. The cathode goes through a 5.1kohm resitor, then to a 47uf cap, then to GND. The relay's (-) side (what is being switched) is also tied into the cathode of the diode.

I hope that information helps. Any other information I might be able to provide please let me know.

THANK YOU ahead of time for your assistance,
Jon, AKA poor_red_neck
 

Offline poor_red_neck

  • Newbie
  • Posts: 3
Re: Can anyone assist in identifying a SMD diode?
« Reply #1 on: April 23, 2014, 01:34:10 PM »
Here is the best pic I could take:
 

Offline Kremmen

  • Super Contributor
  • ***
  • Posts: 1255
  • Country: fi
Re: Can anyone assist in identifying a SMD diode?
« Reply #2 on: April 23, 2014, 03:13:17 PM »
Any ordinary diode will work in that position as long as you can solder it in place. There are no stringent requirements on a freewheeling diode, it only provides a path for the relay coil current to circulate when the switch turns off.
Nothing sings like a kilovolt.
Dr W. Bishop
 

Offline marabut

  • Contributor
  • Posts: 24
  • Country: 00
Re: Can anyone assist in identifying a SMD diode?
« Reply #3 on: April 23, 2014, 06:39:31 PM »
As Kremmen wrote - any small package diode will work. As a reference you can look at online SMD code book:
http://www.marsport.org.uk/smd/mainframe.htm
Probably it's a 1N4150W, anyway.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf