1st Gen Electrical Gremlin Assistance requested

Hey Everyone,

My uncle and I are trying to troubleshoot an electrical issue that we're having with my 2001 1st gen Sequoia Limited 4x4. I'm in South Texas and my Sequoia has had a 5 amp Parasitic draw. Alternator has been changed with a stock Denzo, and we still have the original starter but no changes to the draw after testing it.

- Replaced the battery with an AGM battery on 11/7/23

These are things that have been attempted to locate the source of the 5 amp draw. These are the unsuccessful attempts that have been attempted with no success in finding the draw.

- Pulled every fuse and relay in the fuse boxes, except for the bolted 120, 80 high amp fuse.
- Unplugged/ isolated the alternator and starter.
- Unplugged both passenger and driver door switches.
- Unplugged the overhead driver/passenger light, mpg computer, rear view mirror console
- Unplugged the rear door ECU and harness
- Unplugged the engine to interior harness
- Unplugged the ABS motor.
- Disconnected the VSC / AVS harness
- Unplugged the 5 fuses for the trailer harness/ module.
- Unplugged the Ignition Switch
- Unplugged the fuse for the motorized power folding mirrors
- Replaced All of the fuses

Current Train of thought
- We're about to change the current with a denzo starter.
- We're also suspecting the ABS module.
- HVAC Control Panel is another possible draw, but we're not sure how much that pulls initially.

Parts List Assistance
- Does anyone know the part number to the clips that are going to need to be replaced that's found around the starter area. For sure we're going to be breaking a few and will need to order replacement clips.


We would appreciate any feedback for this issue. Thanks in advance for your feedback.

 

Questions:

• Was there a dealer-installed alarm? There are a couple models some dealers were installing (Securikey, KARR) and they didn't always activate them or give you fobs unless you paid the $1k-2k markup for this $50 add-on. Look for extraneous wiring up under the driver's side of the dash AND behind the driver's kick panel
• Was there any towing add-ons like a brake contoller or similar? Anything you may not have unplugged with the trailer harness?
• Do you hear any sounds (whirring, buzzing, clicking, etc.) when the truck is OFF?
• You aren't doing anything silly, like leaving a wireless OBDII dongle installed, are you? This has bitten others in the ass also
• Links to Sequoia wiring diagrams here; While testing circuits, at any point did the draw stop? i.e. if you remove any fuse to the cab, do you see the vampire vanish? Trying to isolate if this is engine-bay-side, or cab-side...
• Taken from the megathread, which had the wiring diagrams link and has FSM link, did you confirm you don't have water intrusion into the in-dash fusebox via a-pillar/windshield leak like so many others have found? From that thread: These trucks usually don't have a ton of other electrical issues. Hidden corrosion inside the battery/alt cables happens. Sometimes, a couple thousand miles after timing belt changes, people will have startup issues because the crank position sensor wasn't properly tucked away and gets rubbed by a belt (pic). There's also a similar problem with camshaft position sensor under the cam cover, where the belt will rub through (pics). There's the rodent issues mentioned earlier. Occasionally, water leaks can send water down into the ECM behind the glovebox (pics), or into the fusebox inside the cab/dash (pics & pics & pics, it happens a LOT). Many drain/vampire issues trace back to aftermarket add-ons whether the owner knows they exist or not - alarms as mentioned earlier, brake controllers, poorly installed trailer receptacles, those are some big ones.
• Easy VIN-specific parts lookup ... use the bullet points at the top of this thread: https://www.tundras.com/threads/howto-use-the-toyota-parts-system-to-find-order-parts.113808/

 

Hey Shifty thank you for the input. Here's my reply to your inquiries

- I believe it was factory because we didn't get the $1-2K markup. We'll be looking at this possibility as well.
- Towing set up was factory as well. No brake Controller was added. We did review this, but will go ahead and review this possibility.
- We did hear the whirring sounds with the CD player going through it's motions. We tested this before and there was no change in the voltimeter.
- We did not leave the OBDII dongle installed during the testing of the parasitic draw.
- Thank you for the diagrams. The Vampire did not vanish during our attempt, but we'll revisit this once again.
- We have changed the battery and the battery terminal connectors.
- Thanks for the parts link. This will help a lot.