Couple of Problems

[blaire.clinton]

Two problems! First, sweet 100 has eaten 4 batteries in 6 months, and I mean they are done, toast! At first I thought it was the battery, but after the second one I began to think differently. I explained the problem to a Toyota tech, at which time he suggested it was the battery type and that I need to run the Toyota branded battery. After spending nearly $200 I thought the problem was solved, but not even 2 months later I have yet another large paper weight. Problem number two: After a series of breakdowns during our trip moving back to Canada after living in Mexico the last 10 years, this included what was apparently a problem with the fuel pump, ignition coil, and oxygen sensor. Most these repairs were done in the USA, as we drove the 3000 miles home. However once I returned here, I began to notice the vehicle wouldn't start. It turned over, but just wasn't getting the gas. The local Toyota service shop said Fuel pump, but I had just replaced it 2 weeks earlier. Then the battery died and like the others, refused to takeaway charge. I replaced the battery and for some reason that seemed to solve the problem for a couple days until it stalled again. It just would not start! Then after about 20 minutes I tried again, and no problem she started like she never had a problem. I took her back to Toyota, and while trying to explain the problem I got one of the mechanics to have a quick look, and guess what? It would not start! Perfect.. It was like having a heart attack in the doctors office. So after having her in their operating room for the day, they figured out the problem. The Engine Control Unit was the problem. As it turns out, the ECU that was in her, was not the original but from an auto wrecker, which made me wonder why? The previous owner obviously had this problem before. So I needed a new ECU, but after I was quoted $1600 for parts and labour, I decided to find a different option. I did find one in the USA, used but in new condition. After searching and waiting nearly 3 weeks, it finally arrived. I decided to install it myself and save the so called two hours of required shop time Toyota had quoted. I disconnected the negative post at the battery to prevent any arcing, then unhooked the ECU mounts, followed by up plugging the unit itself. I then mounted and plugged in the replacement unit, reattached the battery, turned the ignition. Same problem!!! NOoooo! Ok friends, I love my 100, but after the last few months she draining me. I'm calling upon anyone who can give me any words of wisdom regarding any of these issues. Thanks in advance. BC


From BC

 

[Steve Wright]

Hi BC
I am not a expert, but sounds like the dealers just wanted to rip you off, firs of all it does not matter which make of battery would make it cook.

My guess is its the alternator that is causing the problem, you say you have bought the motor from someone, have the replaced it ? and did he
put a 24 volt one on ?

What you need to do is first tell us if it has two batteries ? and how are they wired, then check the voltage of the batteries at rest, then start it
up and recheck the voltage and report back ?

 

[t1pper]

Hi BC

What you need to do is first tell us if it has two batteries ? and how are they wired, then check the voltage of the batteries at rest, then start it
up and recheck the voltage and report back ?

Does sound like an alternator fault, but I would also check all the earth points and battery terminals clean everything up and check the voltages, when running at rest and when cranking.

 

[Shayne]

My guess is its a short pure and simple , though of course finding it never is . A bare wire is touching metal somewhere allowing a tiny amount of power to seep away constantly but not effecting anything until the battery finally dies because its draining overnight then only getting part charged while your driving the next day . It's just a theory and I'm no expert but it could easily be checked by putting a fully charged battery in the truck while its parked overnight and testing it in the morning . Or maybe someone else more knowledgeable can suggest a better test ?

 

[Towpack]

AS far as your battery problems go, IMO they're either being over charged or over drained. Either scenario is relatively easy to diagnose.

Take the battery(s) off the car and fully charge them with a bench charger. Reconnect them and, using the ammeter function of a multimeter, check the current drain with the the car locked up and any alarm or immobiliser etc armed. It should be >50ma max. If there's no excessive drain, start the car and measure the voltage at the battery terminals which should be >14.4v when the engine is revved.
I'm no expert in the black magic of engine ECU's but, if the alternator is kicking out excess voltage due to a faulty regulator or whatever than this could certainly affect it and other electronic/electrical components. JMO