2006 Chevrolet Impala

KYLE WENSEL, MARCO RAMIREZ & HAYDEN TREE

Workload

• Lab work performed by: All
• This report prepared by: Kyle Wensel
• Workload split: Kyle 34%, Hayden 33%, Marco 33%

Vehicle Details

• Vehicle Year, Make & Model: 2006 Chevrolet Impala LT
• Customer’s Name & Estimate Number: Susan Thomas, 1-16371
• Customer’s Concerns: Switch installed by family relative is used to disengage key from ignition interlock. Wants it removed so they don’t have to use the switch and the switch may be draining the battery.
• Cause & correction: The 10-amp fuse for the ignition interlock was and the switch was draining the battery. Replaced the fuse and removed the switch.

Background

• After we had finished diagnosing and fixing a 1993 Jeep Grand Cherokee, we went to the automotive office to grab a new project. One of the projects we were told about involved Susan Thomas’s Chevrolet Impala and that she was having problem with ignition interlock. We called her and she told us that the ignition interlock wouldn’t allow her to remove the key. One of her relatives managed to install a switch that bypassed the interlock to remove the key. However, she noticed that ever since the switch was installed, her battery was constantly dying and had to be jump started. She wanted to know if we could remove the switch and, also, fix the interlock.

Vehicle Pickup

• We asked Susan if she had time to drop off the vehicle before our class started. She told us that her daughter was using the vehicle, so she would have to pick it up from her. She managed to grab it from her and dropped it off at the Austin building (location of automotive office). Picking the Impala up, there was no problem starting it, so we knew the battery was fine. Once we got it to the shop, we could see that without engaging the installed switch, we couldn’t remove the key for the ignition. Following the instructions from the customer, we were able to remove the key.

Diagnostic Procedure

1. Verify the problem
2. Perform visual inspection
3. Gather data & study it
4. Develop a diagnostic plan
5. Perform Tests
6. Determine the root cause and repair it
7. Verify the repair

1. Verify the Problem

• We tested the switch (picture on the right) a couple of times to verify that the key couldn’t be removed with the switch off. After testing the switch, we verified that we could only remove the key with the switch turned on.
• Testing the battery with the multimeter, we were also able to verify that the switch was causing a parasitic drain. The drain was 400-milliamps, which is over the 30-milliamp range.

2. Perform Visual Inspection

• Since we knew we were dealing with an electrical issue, we looked at the fuses underneath the hood to see if any of them had blown.
• We also checked to make sure that there weren’t any broken, exposed or loose wires. We didn’t find anything noticeable.

3. Gather data & study it

• After our visual inspection, we started looking up wiring diagrams on ProDemand. We looked for wiring diagrams related to the solenoid lock circuit and shift interlock circuit.
• By studying the wiring diagrams, we can determine the location of the fuses, wires connected to both interlock circuits, and look at the location of the solenoid lock.

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Shift Interlock Circuit

3. Gather data & study it

Solenoid Interlock Circuit

Solenoid Interlock Fuse Location

4. Develop a diagnostic plan

• Looking over the wiring diagrams, we figured we should examine the right front kick panel fuse block, see if any fuses have blown. We also want to make sure the relays are working properly and receiving power.
• The other component we decided to look at is the shift interlock solenoid itself. We can determine if it’s receiving power or if the solenoid is broken and needs to be replaced. If it’s receiving power, then we’ll know that the solenoid failed.

5. Perform Tests

• The first component we tested was the shift lock solenoid. We knew from studying the diagram that the solenoid was located in the center console. In order to get to the solenoid, we disassembled the center console.
• Once we reached the solenoid, we tested the solenoid for power, and it was receiving power. It was also functioning just as it should, so we concluded the solenoid wasn’t at fault.

Solenoid

5. Perform Tests

• The first time we were looking for the solenoid fuse, we couldn’t find its location. Every other fuse and relay we examined were in good condition, so we looked at panel diagram again.
• Looking over the diagram, we saw that it was hiding in the corner behind the relays (red circle in picture). We tested the fuse and noticed it was only getting power on one side.

6. Determine the root cause and repair it

• When we saw that the fuse for the interlock solenoid was only receiving power on one side, we pulled it from the fuse block. Pulling it out we noticed it had blown and determined this to be the root cause. We decided we would pull a 10-amp fuse from our shops inventory to use as the new fuse.

7. Verify the repair

• After installing the new fuse, we checked to see if the key would come out of the ignition without the installed switch. We tested about 5-6 times turning the ignition on and off and didn’t have any problems pulling the key out. We pulled the switch out of the system and tested the battery again to make sure that the battery wasn’t draining. The drain was shown as 10-milliamps, which is under the 30-milliamps specification, so after everything passed, we reassembled the center console. Once everything was reassembled, we brought the vehicle back to the Austin building and informed the customer that their vehicle was ready for pickup. We informed her of the repairs before hand and she expressed how grateful she was for the repair we made.

Reflection & Analysis

• What parts of this process went well?
• Being able to use the wiring diagrams provided by ProDemand, we were able to locate the fuse that was causing the ignition interlock to fail.
• Which steps were most critical to your diagnostic & repair process?
• Gathering data and performing tests were critical during the process. Without having the right diagrams and performing tests, we wouldn’t have found the where the fuse that caused the problem.

Reflection & Analysis

• What kept you from being as effective as you could’ve been?
• When we couldn’t find the fuse the first time, that really set us back. It would’ve been beneficial for us to make sure we read the diagram right and not missed it.
• Now that you can look back on how this project unfolded, what would you like to different next time?
• I would like to become more familiarized with going over wiring diagrams. It would be beneficial to make sure I know the first time where to look when finding electric components to test.