1993 Honda Accord Automatic Transmission Control Unit Circuit Diagram

Hi Folks,
The AT Control Unit on my 1993 Honda Accord has a busted resistor (R41) in it. Without any kind of printed circuit diagrams, I am unable to
determine what kind of resistor it is. Can anyone help with either a printed circuit diagram or the resistance value?
Thanks. Rocky Dada
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
RockyDada wrote:

the junk yard.
if the resistor color codes are still legible, you can read them and buy another resistor the same value. if they're toasted, the junkyard is your best bet. regarding wattage, size matters. if the replacement is the same size, you should be fine.
http://www.honda-tech.com/zerothread?id –2851&uid™9378256&dir=1&postid122854
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
jim beam wrote:

http://www.honda-tech.com/zerothread?id –2851&uid™9378256&dir=1&postid122854

you'll have to judge the colors for yourself [not sure my monitor is up to the task]
http://xtronics.com/kits/rcode.htm
1/2 watt, judging by an unburnt neighbor. modern resistors are smaller for the same wattage than older resistors like this. as long as they're not too big to fit, use the largest resistors you can for highest wattage.
one thing not clear from that first link is the % tolerance band color scheme - in this case 5% [gold]. read starting from the end opposite the % band. also, the value has to make sense based on preferred values. all resistors use certain values like http://www.electronics2000.co.uk/data/itemsmr/res_val.htm
if your read value is not on that list, you're reading from the wrong end!
get back if you have any more questions. color pics help a lot.
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks a lot for the quick response back. Luckily, I had access to another such unit with the same resistor in good condition. It is exactly the same as the one to it's left. The resistor is a 15 ohm, 5% tolerance, 1/2 watt resistor. I plan on getting it from the local Radio Shack store and work on it tonight. Will let you know how it goes.
Regards. Rocky Dada
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
RockyDada wrote:

----------------------------------
While you're in there, why not replace some to the capacitors? They're famous for eventually exploding, and then it's even harder to figure out what they were unless you find the right web page. You can spot the bad ones (which have been running HOT) because the plastic label has regressed, leaving the top of the caps naked.
What wrecked the resistor in the first place?
'Curly'
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I don't find any other components to be in bad shape but thanks for the advise.
Rocky Dada
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
'Curly Q. Links' wrote:

yes, but only if they show signs of distress. generally, the quality of honda componentry is very good, and one of these factors is capacitor size. in the past when i've replaced them, i've had difficulty sourcing some of the same types honda uses, and if i do find them, the replacement has physical size issues.

good question! i believe that resistor is in the output chain, so i'd definitely check for correct operation of whatever it's supposed to be driving.
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Well folks, it did not work out even after replacing the resistor. I guess I will have to bite the bullet and buy a new (or used) TCU since I don't see any other obviously distressed components. If it's an IC, I would definitely not know how to diagnose or fix it. Thanks for all your help though.
Regards. Rocky Dada
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
RockyDada wrote:

a reason - and chips are definitely a candidate. make sure your solenoids are working ok before you discard the tcu.
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I got into this late, but that is a big 10-4. That resistor was dissipating several watts (I would guess 5-10 watts, judging by the surroundings) and that means a short somewhere. A shorted capacitor or power transistor is the way to bet.
Wrecking yards are the solution, for sure. The circuit board has suffered more than I like to see, so even finding and replacing the shorted part would be a partial solution.
Finally - not to worry you too much, but it is worth mentioning - the short may be external, like the wiring to the transmission. If so, the replacement will do the same thing. It may be worthwhile to remove the cover of the replacement TCU so you can shut down power as soon as the resistor smokes (if it does). Once that is sorted out, replacement of the resistor should get you working again.
Mike
Add pictures here
✖
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.