Looking to replace this diode that I am pretty sure is blown since I have tested the diode in both directions and get a reading where the one next to it does not. This is for a LAMP ASSY, TELLTALE for a Toyota check engine light on the dash. Its a Black diode with a blue stipe on the positive side or direction of current flow with the inscription of IE3C.
Hello,
Unfortunately I could not identify this diode.
with a Multi-Meter I measure the following when connected in the circuit:
0.22nf on cathode side Anode (a) – nothing in reverse (b)
0.582 volts (a) and 0.070 Volts (b)
not sure what size diode I should get to just wing it for coverage. Some time when I am back in the car I can measure supple voltage at the plug. I know it is not 12v as that is what blew the diode.
Can you provide an image or two of the part? Both a close-up as well as showing some of the surrounding circuitry can often be helpful.
Sorry it took me some time to check back. Attached I have 2 photos of the front and back of the circuit. The back side I had to attach a red wire to fix the path I burnt up when testing the bulb with 12v which was too much and fried one leg of the circuit and the other the diode that needs to be replaced with the marker marks. If a closer picture is needed I can remove it from the car and add more and also do a voltage test around the diode to find true system voltage in this area.
I would say seeing if you are able to get the system voltage that would help in IDing an alternative.
Also if at all possible see if there is information on expected current for these we can select an option that would be able to handle the circuit.
Hi @whitetigr90 I would think 1655-SB2060CT-ND (click here) would be a good safe replacement. This is rated 60V @ 20A, physical body size: 8.5mm x 5mm. Please review datasheet specifications before ordering. Although as a guess each bulb (and diode) is pulling between 200-500mA when on, incandescent bulbs act almost like a short when initially powered (before the filament is glowing) and this initial spike current can be what burns out the diodes if they are not rated for enough current.
If your diode bodies are larger than this option provided, we may need to go with a larger option which can provide for more current handling. If so, please provide physical measurements and we can select the largest current rating we have based on that size. I see this diode does have a 8.3 ms, half Sine pulse, TC =25°C 30 @ 300A so I would think this would be safe, but would be best if we match the size or go larger.
is expected current when one of the lightbulbs are not lit or is going to be when one is lit.
Hi whitetigr90 , current when lit. You’re multimeter may have a MAX feature which should give you the max current, which will include the surge current. Otherwise getting a current rating when bulb is lit should be good enough along with the physical size of the diode.
See provided picture. I did a voltage test on the circuit when the car was in acc mode and power was sent to light all the bulbs up and then again with the car running. I provided a voltage reading of a good diode and the bad which are both the same number on the diode, For reference look at the above picture and the blue/black mark is now the good circuit for the check engine and the bad circuit is to the left so I know it is bad but needs the replacement. I am still learning but to me it looks like the diode has to handle 14+ Volts and has a voltage drop of 10 volts when car is running and car door is open. Oh yea might not have mentioned that when the door is closed the bad diode that controls the bulb with shut off. This test was done door open.
