I made it to Southworth and got off the ferry and reached Belfair. I noticed that my audio system had gotten significantly quieter, and the only reason for this was because my battery was draining. I had already gone through this before back in January one evening while out at Neah Bay so I knew what to expect. I've got a blog post of that experience here along with video from my Contour camera. Anyway, I stopped at O'Reilly and asked them to test the charging system and the voltage regulator tested bad. The voltage regulator is inside the alternator and steps up or down the alternator voltage output to keep it roughly around 14.5 volts while the engine is running so that the battery remains charged at 12.6 volts. 14.5 volts compensates for loss due to resistance in the wiring and current draw. My alternator's output when the engine was running was about 11v, which is essentially a discharged battery. I bought a new battery in case I needed to swap my 6 year old Optima Yellow Top out while on the road; besides I had been planning on buying a new one anyway for an auxiliary battery.
After I was finished there I headed west towards Hwy 101, but it was getting dark and I knew I wouldn't make it so I headed to another O'Reilly in Shelton. I replaced my battery in the parking lot there and asked one of the employees to test my alternator again; same result as before. I went inside and bought a new battery to alternator cable and some battery post shims. I had also bought a new alternator with the intent on replacing it, but decided to just replace the cable and inline circuit breaker first. My thought was that the circuit breaker was causing too much resistance for the alternator to effectively recharge the battery. So I got to work replacing the Optima and installing the new AGM battery I bought on the way out.
The work itself is simple, but I was doing it in the dark and using a headlamp. I also was replacing the stock alternator to battery cable with a new one, so it took a while. After I finished, I checked the LCD on my DC inverter and it read 14.5 volts with the engine running; success!
|This is my actual inverter; its mounted in the rear of the cab. See the display? 12.2 volts read from the battery.|
I started out Friday night last weekend, thinking it would take several hours, but I was way off. This was so much work; and I tried to break it up into three parts: 1) Auxiliary battery and battery isolator, 2) Cab electrical and accessories, 3) Engine bay wiring, fuse box, alternator swap and new battery.
The photo below showed what the work looked like when I started on Friday night, and as you can see it was a mess.
Where to put the auxiliary battery?
The auxiliary battery location baffled me; I had been reading the Tacoma forums and lot of the owners and enthusiasts were installing 2nd or auxiliary batteries under the hood, on the passenger side.
In the photo below, taken from yotatech.com member BajaTaco's write up on dual batteries in 1st Gen Tacoma trucks, you can see how he added a second battery under the hood on the passenger side. Unlike mine, he has no factory equipment there.
I would do that, but the anti-lock brakes actuator was in the way and this couldn't be relocated. I tried putting it in the cab behind the driver's seat but I just didn't like the way it looked, and settled on the truck bed.
|Decided to reuse my Optima since it still worked great|
|Battery up front-left, axe mounted above it, high-mount jack, fuel and water cans|
It involved routing a 2 gauge wire under the chassis to the bed of the truck, drilling holes large enough to add grommets that would allow the wire to fit through (to prevent cutting the wire insulation and grounding out). I routed the wire from the primary battery to the bed and connected it to the Battery Doctor isolator's main (+) terminal, and connected the aux (+) terminal to the Optima's (+) terminal. I then connected the Optima's (-) terminal to a battery ground wire I attached to the bed. I tried to use the side post terminals rather than the top so I could cap the top posts with factory caps to prevent arcs.
The battery isolator is pretty cool; it separates the main starting battery from the aux battery, but lets the main battery charge the aux battery. If I hook accessories up to the aux battery, it prevents the draw from going to the starting battery. I can also hit the override/reset switch on it and use the aux battery as a starting battery or a jump start battery if the main goes dead.
The cab electrical required running another lead back from the aux battery's (+) terminal, under the bed to the cab. There, I have it ran to a 100 amp inline circuit breaker and a power distribution block. The truck's audio system amplifier and DC inverter are connected to the power distribution block; this way they only get power from the aux battery. If I'm at the coast and I want to power accessories, I never have to run the motor to keep the primary battery charged, and never have to worry about a dead battery again.
- The audio system alone was crushing my alternator and primary battery. The factory system was four speakers and a typical AM/FM/CD head unit. I got rid of all of that and replaced the front speakers with new 5.25" speakers, and replaced the rear with the same.
- I took it further after removing the rear seats and cut out holes large enough to fit new 6.5" Kicker speakers, and installed a new 8" subwoofer in the tool compartment on the left side, behind the passenger seat. Goal was to keep it as factory looking as possible.
Additionally, my 1100 watt sine-wave DC inverter and fog lights would be connected to the power distribution block. At the moment, the lights are hardwired to the primary battery with inline fuses, but I'm going to route them through the fuse box with a relay and fuse to clean up the wiring.
Under the hood
Now it was time to get started on the work under the hood.
- I would have to route that 2 gauge wire from under the chassis up to the engine bay and connect to the primary battery.
- I also decided to replace all of the charging system wires with heavier gauge wires; this meant the main starting battery's (+) to alternator output terminal wire, fuse box to battery (+) wire, and fuse box to alternator output terminal wire.
- Sleeving and using heat shrink tube on the ends of all of the wires for aesthetics and to prevent from damage
|New Super Start AGM battery with 2 gauge sleeved wires|
|Notice the top left, below the black cylinder is the ABS actuator|
One other detail I added was a new 2 gauge battery ground wire from the alternator's mount point to the vehicle chassis. The reason I did this was because the Tacoma only had one ground wire that ran from the battery to the engine block. The block had multiple smaller gauge wires to the chassis, but that was it. I added the second ground wire as recommended in another forum I read. You can see it in the photo directly below of the alternator; its the black wire.
The alternator was going to be replaced also. The stock alternator was a 60 amp one, which was insufficient and I had chosen a GM 130 amp CS-144 alternator. That's right, a General Motors alternator. A lot of other Tacoma and 4 Runner owners have done this since the CS-144 is a direct bolt in alternator that requires almost no reconfiguration except a wire harness conversion to fit the Tacoma's oval style 3 pin harness.
|Stock alternator here, much smaller than the GM alternator|
|The GM alternator I'm going to install; has a fan built into it to keep it cooler|
|Can you identify the problem?|
First, I checked the LCD on my inverter, and an LCD battery gauge/USB charger I recently bought on Amazon; both said 12v with the engine running. The engine should have been 14.5v but the alternator was not producing sufficient voltage to recharge the battery properly. This was a problem for operating the vehicle, and was going to damage the battery since anything in the 11-12v range is a discharged battery (remember a properly maintained battery should be 12.6v when the engine isn't running).
I checked the connections everywhere, did some more reading, and spoke to a Toyota mechanic/expert from JustAnswer who felt it was a few things. Primarily was the gauge of the wires I had used from the fuse box to the battery, and fuse box to the alternator. The 2 gauge wire from the alternator to the battery was fine he said. He also felt the 3/8 copper terminal lugs I used might have been too large. Well, ok. Some more parts I had ordered from Amazon arrived yesterday, and I would fix the issues above when I swap out the alternator.
|Heavy shrink tube, GM-Toyota alternator wire harness adapter, inline fuse for the 2 gauge wire to the aux battery another inline fuse back to the inverter and amplifier, power distribution blocks, 140 amp fuse for the alternator, and 4 gauge wire|
I decided last night was a good night to get started on the alternator swap so I got started around 8:30pm. I started by removing the battery and placing it on a charger to get it back to capacity. Then started by disassembling the fuse box and removing the wires I upgraded. The higher output alternator I was installing would also require a higher amp fuse since it was 130 amps and the stock fuse was only 120 amps. I removed the stock fuse at this time, which had blown the day before when I let a battery cable dangle and touch the chassis.
|The stock 120 amp alternator fuse here blew the day before|
|Stock alternator shown here with the belt tensioner pin installed still|
|And here it is with the pin removed|
Someone on one of the forums I had been reading about upgrading the wires and installing the GM CS-144 alternators in Tacomas had used the term "shoehorn" as a way to describe trying to fit one of these alternators in. That's a great way to describe it, because its so much larger than the stock alternator, I had to shoehorn it in alright. I had to remove the mounting bracket and force the tensioner bracket down a few inches to accommodate the new alternator.
|This was more or less a mock up to see how it would fit first|
|Side by side comparison of the stock and GM alternators|
Today I finished the alternator install with some spacers I bought; actually a nylon washer and a steel washer I drilled out a bit. Both of them filled the gap between the right side of the mounting bracket and the alternator case.
I also finished all of the wiring, which included a new and larger gauge battery ground to engine block wire, and oversleeving the battery (+) wires to the starter and the alternator wire harness). I also put some heavier heat shrink wrap over the battery (+) wire near the terminal connector.
|The heavier heat shrink tube is the pink sleeved wire|
|Here's a good view of the alternator with the drive belt around it|
|This is the fuse box wire, and the battery wire is underneath it|
I also replaced the stock 120 amp fuse with a 140 amp fuse. The gap here is from when I blew it on Sunday when I got careless with wiring. I bridged it for a little bit so I could drive to the store; pretty stupid I admit but hey, YOLO.
Well, I'm finished with this monstrous project. I worked all night Friday, most of Saturday and most of Saturday night but I've finished with the alternator, wiring and auxiliary battery. Friday night I finished up with the alternator, but when I went to start it on Saturday morning, it still only was charging 12.2v. I started to do some testing, but the idea that the heavier gauge wires were the problem just weren't making much sense to me. I had a hunch it was the 3 wire harness attached to the factory wire loom because in the past, the battery light has never come on when the alternator had problems. The battery warning light also was not coming on when I cranked the key over but didnt start the engine.
To test this, I took my multi-meter and continuity tester and tested the three wires; only the white white measured any continuity at 12.6v. I then took the yellow wire from the 3 wire harness, cut and stripped it, and grounded it against the battery (-) post. The battery light on the dash came on!
I then cut and stripped the red wire and spliced it with a spare GM two wire harness I have for a CS130 alternator.
|Red and yellow wires both spliced from the OEM harness into the CS130 harness|
|Looking up from the bottom; that's the two wire CS130 harness and only tempoarary|
Now that the significant work was done, it was time to move on to cleaning up the wiring and close the hood back up. Saturday night I got started on removing the 2 gauge wire I had ran underneath the truck a week or so before. While it was heavy duty, it was too rigid and I was unable to bend it and splice it into an inline fuse.
I did some more reading online and found a thread in a forum where one guy purchased a four groove pulley that fit the GM alternator and had a shop that specialized in alternators swap drive pulleys out. I ordered a new belt drive pulley online from Quick Start Alternator Parts with four grooves and took it to West Seattle Auto Works and had them swap the drive belt pulleys out. These guys are awesome, the work only took a half hour or so and only cost $65. Now my alternator spins faster since the drive belt pulley is smaller, which also means my belt has more length in it. The pulley I ordered is shown below, although its only a stock image.
At this point I can say I'm done with the electrical work. Its charging at 14.2-14.5v while the engine is running, both batteries are charged at 12.6v when the engine is off. I still need to hook up my fog/driving lights, but am going to use new wires and a relay bank for that. The relay bank will have a relay for the fogs, a fuel pump cut-off relay for a switch I plan to install for anti-theft purposes, and a spare for future needs (shown below). I bought it on Amazon for like $70, although its no longer available right now.