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Why the Main Relays are design the way they do.

It's a known fact that the relay fail from the poor solder application process. When the circuit boards are mass dipped into a pool of hot solder the solder can seep into the circuit board creating bad solder application. Unlike high quality double side cu-lead found in many computer product, the main relay board is prone to this type of bad solder application. 


How the terminals should be soldered.

Inside the vehicle, the solder has to go thru the heating, cooling and vibration not to mention other inefficiencies such as poor electrical part design, poor positioning of the solder joints and poor selection of parts which only helps to increase heat. 

Solder joint's can succumb to resistance.  By this time the solder is damaged. You can see by the way the solder melts compared to other solder on the circuit board.

There are simple solutions for the main relay manufacturer. They simply have to check the joints for quality standards on critical joints. The critical joints are the relay coil and resistor terminals.

The most drastic method for car owner is to remove the previous solder and apply new solder but without letting the solder seep thru the terminal wire and the base material. The way to do this is to block the solder from flowing thru the circuit board. In this image below a copper wire is used to wrap around the terminal to seal the joint. This method isn't required if you choose a different type of solder.


 You won't be needing a soldering iron that exceeds 50-Watt or temperatures greater than 600F.  This is because of a cheap circuit board and the unnecessary need to remove the thick solder terminals, usually located on the edge of the circuit board. The terminals on the edge of the board are large enough to dissipate heat on its own thus these joints will not be affected by the usual problem of dry joint.   Also, if you are using a 100W or above soldering iron the cu-lead may also lift. Remember, do not be tempted simply touch the hot iron on the joint. This will only fix the joints temporarily and may lead to a serious problems, developing symptoms similar to that of a defective ignition switch. We highly recommend that you fix it right. 

Picture of where to solder

There are many circuit board designs on cars that generate heat. Such one example is the dimmer control unit or the fuel cut-off relay. Some of these generate less heat than a relay but yet have breath holes on their casings to vent air. If main relays were made with the ability to dissipate heat then there would be few main relay related starting problems. There are no explanations why main relays are made this way even when reports of this problems were coming in.

When we setup this website in 1999 for the main relay problem, we had in mind that this site will be obsolete in a few year. It's been six years with 34,000 hits or 4551 page views per month (clocked by Tripod hosting) and this site is still being visited. Eventually, I will moved this site completely to comply with Google's rules.

The control units and relays are selected from a worldwide selection of electronic makers. Each maker designates a different scheme to dissipate heat. 

It's still unknown why some cars such as the Sterling (unknown year model) have a very identical (Mitsuba) main relay mounted in a different location - right under the steering column but yet havenít seem to have the same problems like the Accords, Civics or the Integra in the 1986 year range. Itís a mystery to why the part supplier responsible wonít create a website for people to self diagnose their out-of-warranty vehicles. People have been upset by this problem for many years. Intermittently, their cars wouldnít start in gas station or parking lot. But under the light of all this don't let this problem bother the Honda owners. Overall, Honda is a great company that pays attention to it's environment. Toyota is also a good example company that is looking forward towards make the rest of its fleet hybrid.

The main relay is not a main issue the Honda Company has to address. Honda motor co. should be focusing on is its ignition system. This can range from the ignition switch to the coil, igniter or rotor.  Several cases people reported stalling in the middle of an intersection. Others have bad misfortune of stalling in the far left lane in a busy freeway sometime at 70 mph. Iíve been on call to several cases of people stranded in busy freeway only to find their ignition system have failed them. At all these instances, we had to tow the car or adapt a system for low speed travel, or simply replace the rotor (two cases.)

Author’s background:

With an education in Auto mechanic, electronics repair and robotic design in Delta College, the author continues with electrical engineering course for a few semester in the University of Long Beach in California. 

"I've grown up with Hondas since 14.  I admire its ability to be electrically and mechanically environmental friendly cars (not quite the same today). It was the first car that Iíve known to be durable but yet gentle to the touch of our hands. 

Chemicals used to make the plastics, the PCBs and the rubber parts surpass those found on some other automaker based on the price per part. Iím a fan of cars that are environmentally friendly. Some vehicles are not environmentally friendly because they are difficult to renew and simply are disposables. The quality of life can't be accomplish just by developing low cost cars but rather those that won't create long term problems such as (paralysis or cancer). The ongoing fuel crisis should begin to fuel Honda and Toyota to look harder into electric or electric hybrids vehicles. The overall great car should reflect its ability to make the world a better and productive place to live. "

"Toyota is now, I believe, surpassing Honda in its ability to develop safe and environmentally friendly vehicles based on the NHTSA. Toyota has set new standards in auto design and engineering. I hope Honda Learns from Toyota and improve itself."

Add your comments, suggest corrections or clarifications. Thanks.
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