Mystery Battery Draw Can Drain Your Productivity - BodyShop Business

Mystery Battery Draw Can Drain Your Productivity

A vehicle you repair that seems "good to go" can sometimes come back to haunt you with concerns that may or may not be related to the repair.

How much time is wasted in your shop tracking down obscure problems and fixing them? A vehicle you repair that seems “good to go” can sometimes come back to haunt you with concerns that may or may not be related to the repair. Electronic and electrical systems can especially generate hard-to-diagnose problems.

Factory information is the answer. In many cases, a factory technical service bulletin (TSB) has been published that provides a quick solution to a known defect or issue.

Customers frequently come back, honestly believing that your repair is the cause of some new problem. But the problem may be a previously diagnosed “glitch” known to exist on a particular vehicle. Armed with OE information, you can protect your shop and generate additional revenue by fixing the problem – not to mention enhance your relationship with the customer.

Here’s an excerpt from a TSB published by Toyota describing an electrical problem with some 2011
Sienna vans.


Some 2011 Sienna vehicles’ batteries may lose their charge overnight even though they were properly closed and locked with the interior lights turned off. In the event that a parasitic draw exceeding two amps is discovered and the A/C compressor clutch is confirmed to remain on with the ignition off, this bulletin provides a repair procedure involving circuit inspection and replacement of the integration relay.

Certain 2011 Toyota Sienna vans produced before the production change effective VINs shown below.

 2WD  5TDKA3DC#BS008690
 4WD  5TDJK3DC#BS027553

Parts Information

 82641-08050  82641-08071  Relay, Integration  1
 82641-08030  82641-08080  Relay, Integration  1
 82641-08040  82641-08090  Relay, Integration  1
 82641-08060  82641-08100  Relay, Integration  1

Required Tools & Equipment
Manufacturer’s diagnostic scan equipment or suitable equivalent.

Applicable Warranty

  • This repair is covered under the Toyota Comprehensive Warranty, which is in effect for 36 months or 36,000 miles, whichever occurs first, from the vehicle’s in-service date.
  • Warranty application is limited to occurrence of the specified condition described in this bulletin.

Service Information
Always refer to ALLDATA Collision for safety procedures, identification of material types, recommended refinish materials, removal and installation procedures. Always refer to the manufacturer for questions relating to applicable or non-applicable warranty repair information.

figure 1 - b41 connectorInspection Procedure
1. Confirm the vehicle is produced before the VINs listed in the table to the left.
2. If an abnormally high parasitic draw of approximately two amps is confirmed with ignition key in the “OFF” position, proceed to Step 3.
3. With the ignition key in the “OFF” position, disconnect connector B41 and verify the A/C clutch audibly clicks “OFF.” If a click is heard, proceed to Step 4 (Figure 1).
4. From the front side of the connector, confirm battery voltage on A/C clutch B41 connector. If battery voltage is present, proceed to Step 5.
5. Replace Integration Relay.

Integration Relay Replacement
figure 2 1. Release the black retaining tabs at the top of the relay using a pick or blade screwdriver (Figure 2).
2. Grasp and pull straight up on the integration relay after both tabs are released.
3. Release all three connectors at the bottom of the integration relay (Figure 3).
Figure 34. Connect all three connectors into the bottom of the new integration relay and push the relay assembly down into the junction block until both black tabs click into place.
5. Confirm normal compressor clutch on/off operation with engine running and A/C on, and with vehicle turned off.

Dan Espersen is ALLDATA’s senior collision program manager and holds an AA Degree in automotive technology. He has 46 years of experience in the automotive industry, including 19 in the collision industry.

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