Questions and Answers
Another Honda Accord "S" Light On
Q. Dear Vincent, I have a very similar problem to what I just read posted on the "About" site; I also read your answer. I have a 1991 Honda Accord EX with automatic transmission and only 49,600 miles on it. I have been the only owner and it has been regularly serviced.
In November, the sport mode light came on and the lower two gears dropped out. I could still shift through all gears using the T bar. On the day that I brought it to my mechanic, all the gears came back into functioning. He found a short in the microcomputer module that operated the automatic seat belts, which he replaced, but said that it should have nothing to do with the main problem that I was having.
Since then, the transmission operates properly for the most part, but the sport mode light comes on, stays on for about a quarter of a mile, then shuts off. But it has also occasionally downshifted while in fourth gear with the sport mode light coming on. In addition, the dash board lights for the gears sometimes will not go on when I shift the T bar into or out of reverse, unless I wiggle the T bar slightly to the side.
My mechanic wants me to take the car to a transmission service, because he doesn't do transmission work and says that the electronic module (or modules) that are not functioning properly are really more the work of transmission specialist.
He also suggests that I do myself a favor and buy a new car. (As an aside, curiously, he has offered to buy this car from me as he deals a bit in used cars. Needless to say, although I have been with him for about 25 years, his interest in taking the car off my hands troubles me a bit. But everyone that I know out his way has absolute confidence and trust in him. And I would like to continue to do so myself.)
I'm not at all mechanically inclined and therefore incapable of doing any work on the car myself. What do you think the problem here is and what would you recommend as far as servicing it?
A. On the bright side, the fact the "S" indicator light came on indicates it is an electrical problem rather than a mechanical one.
When the A/T control unit senses an abnormality in the input or output systems, the "S" indicator light in the gauge assembly will blink. However, when the Service Check Connector, located to the lower right of the glove compartment, is connected with a jumper wire, the "S" indicator light will blink the problem code when the ignition switch is turned on.
When the "S" indicator light has been reported on, connect the two terminals of the Service Check Connector together. Then turn on the ignition switch and observe the "S" indicator light.
Problem codes 1 through 9 are indicated by individual short blinks, Problem codes 10 through 15 are indicated by a series of long and short blinks. One long blink equals 10 short blinks. Add the long and short blinks together to determine the problem code. Let me know what code you get and I can tell you what it means.
If you don't think you can perform the self-diagnostics yourself, then I would recommend taking it to a Honda Dealer and let them diagnose and repair the problem.
There is a Technical Bulletin issued by Honda that may apply to your vehicle as well.
Technical Bulletin #:289
Subject: Wrong Gear Starts
Application: Honda, Accord
Date: Jan 1995
Honda Accord PX4B Wrong Gear Starts
- Starts in 3rd or 4th gear
- "S" light on, but not blinking
- No codes in computer (A/T control unit)
- Shifter interlock control unit buzzing
Check to see if your vehicle falls into any of these ranges:
U.S. Built 2 Dr Models up to VIN 1HGCB72 _ LA039050 U.S. Built 4 Dr Models up to VIN 1HGCB76 _ LA121350 Japan Built 2 Dr Models up to VIN JHMCB76 _ LC104599
If it does, there is a modified Transmission Control Unit (TCM) that will fix the problem. A Honda Dealer will be able to fix you up with the correct TCM.
Thanks very much for your reply. I brought my car to a new mechanic on Friday. He found that the control unit was not giving any codes, then called a transmission specialist friend, who said that he had seen several failures in 1991 Honda Accords of control units that all came from a particular factory in Georgia.
My mechanic said that he reset the codes and the gears operated very well. He is obtaining a used control unit to see if he can solve the problem at the lowest possible cost. I shall also pass along to him your response. I think that it confirms his own findings.