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Multiple electrical problems on this one.This truck had everything from lights coming on after shutdown to intermittent ...
10/07/2026

Multiple electrical problems on this one.

This truck had everything from lights coming on after shutdown to intermittent no-starts, radio and power steering loss, and eventually a dead battery.

Testing found seven modules contributing to the drain. Network testing isolated the primary fault to the instrument cluster. The cluster was waking the CAN network, which then woke the BCM and several other modules.

The instrument cluster had failed and requires replacement.

Multiple symptoms. Follow the network. Find what wakes up first.

New Case Study Is Up → [https://youtu.be/Lcb1GJURIuA]Engine dies when the headlights or A/C are turned on. The washer pu...
10/06/2026

New Case Study Is Up → [https://youtu.be/Lcb1GJURIuA]

Engine dies when the headlights or A/C are turned on. The washer pump also runs with the headlights and turn signals behave erratically.

2010 Lincoln Town Car
Key points:
• Headlights caused the PCM to completely lose communication.
• Circuit testing showed the lighting and washer circuits were finding an unintended ground path through each other.
• Testing isolated the problem to a failed Ground 102 connection. Providing a known-good ground immediately restored proper operation.
• The ground connection was disassembled, cleaned, and restored.

Results: Headlights, turn signals, hazards, washer system, PCM communication, and engine operation all returned to normal.

Hatch window stopped working. The motor was running, but the window wasn't moving.Testing confirmed the wiring was intac...
10/01/2026

Hatch window stopped working. The motor was running, but the window wasn't moving.

Testing confirmed the wiring was intact and the regulator assembly along with the glass moved correctly.

The window motor was removed and powered directly. The motor operated internally, but stripped gears prevented it from driving the regulator.

Failed motor, not a wiring or regulator problem. Test the system. Replace what actually failed.

Two alternators later, still not charging.The charging failure started immediately after the vehicle was used to jump-st...
09/29/2026

Two alternators later, still not charging.

The charging failure started immediately after the vehicle was used to jump-start another vehicle. Two alternators had already been replaced, but the problem remained.

Further testing confirmed the alternator itself was capable of charging and the control wiring, computer powers, grounds, and communication circuits tested correctly. The PCM was trying to command the alternator to charge, but couldn't complete the task.

The fault was isolated to a failed PCM alternator driver.

Two alternators replaced. Neither was the problem. Test the circuit before replacing the part.

Intermittent engine shutdown traced to the coolant level circuit.The truck would intermittently stall after warming up, ...
09/28/2026

Intermittent engine shutdown traced to the coolant level circuit.

The truck would intermittently stall after warming up, especially while pulling a loaded trailer. Each shutdown was preceded by an engine protection warning.

Testing during the failure showed the coolant-related fault counter incrementing with each shutdown. The coolant level system was isolated and bypassed with a resistor, and the truck then ran without issue.

Duplicate the failure. Watch the data. Isolate the circuit.

New Case Study Is Up → [https://youtu.be/J8g1UUjz5a0]Vehicle: 2014 Dodge Challenger 5.7LClient concern: Transmission stu...
09/25/2026

New Case Study Is Up → [https://youtu.be/J8g1UUjz5a0]

Vehicle: 2014 Dodge Challenger 5.7L
Client concern: Transmission stuck in limp mode with only first gear and reverse.

Key points:
• TCM was offline with multiple communication faults.
• CAN communication and ground tested correctly.
• TCM power intermittently dropped from battery voltage to less than 0.5V.
• Testing isolated the intermittent power loss to the transmission relay.
• A higher-quality relay was installed and the vehicle was repeatedly heat soaked, cold soaked, started, and driven to verify the repair.

Result: Seven months later, the problem has not returned.

Even the headlights can shut an engine off.This engine would die and activate the windshield washer pump whenever the he...
09/23/2026

Even the headlights can shut an engine off.

This engine would die and activate the windshield washer pump whenever the headlights or A/C were turned on.

Testing showed that applying power to any circuit in the right front headlamp assembly caused PCM communication to drop out and the washer pump to activate.

A bypass ground at the headlamp eliminated every symptom.

The circuit was traced to a poor ground connection at G102/G103. Correcting the connection restored normal operation.

One bad ground. Multiple unrelated symptoms. Test the circuit, find what they have in common.

Intermittent communication fault traced to corrosion.This body computer was losing communication with the radio receiver...
09/21/2026

Intermittent communication fault traced to corrosion.

This body computer was losing communication with the radio receiver, even though the scan tool could still communicate directly with the radio transceiver.

Testing the dedicated single-wire communication network between the two modules showed incomplete messages at the BCM.

The circuit passes through two in-line connectors. One was located in an area with a history of water intrusion, so testing was directed there. Inspection found corrosion affecting the communication circuit at the connector.

The damaged connection was repaired and normal communication was restored.

A module communication fault does not necessarily mean a failed module. Verify the network. Isolate the fault. Repair what actually failed.

Buttons stopped working?Steering wheel controls, window switches, HVAC buttons, seat controls, radio controls, and other...
09/20/2026

Buttons stopped working?

Steering wheel controls, window switches, HVAC buttons, seat controls, radio controls, and other switches can stop working for a lot of reasons.

Sometimes it is the switch. Sometimes it is wiring, a module, or a communication problem somewhere else in the vehicle.

Replacing the button is easy. Finding out why it doesn't work comes first.

Address

8307 Dayton Pike
Soddy-Daisy, TN
37379

Opening Hours

Monday 11am - 8pm
Tuesday 11am - 8pm
Wednesday 11am - 8pm
Thursday 11am - 8pm
Friday 11am - 5pm
Saturday 12pm - 5pm

Telephone

+14234010588

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