Automotive CAN/J1939 + Android/Embedded Engineer

# Automotive CAN/J1939 + Android/Embedded Engineer for Heavy-Duty Truck Remote Equipment Control We are developing a vehicle-mounted control and telematics system for heavy-duty vocational trucks, primarily **Peterbilt 567 and Mack Granite** platforms. We already have the primary tablet hardware, documentation, CAN access strategy, and an existing software application. We are looking for an engineer with hands-on experience in **heavy-duty vehicle electronics, SAE J1939/CAN, automotive I/O, Android/embedded systems, and body equipment controls** to help us validate the architecture and take the system from prototype to a reliable production-ready installation. ## Existing Hardware / System Our current hardware is a **7-inch N777S rugged Android vehicle terminal** running Android 13. The tablet provides: * CAN bus interface * 3 digital outputs (GPO/DOUT) * 3 digital inputs (GPI) * Open-drain GPO outputs * Maximum GPO sink current of approximately 500 mA * 8–36 VDC vehicle power input * ACC/ignition input * Bluetooth * RS485 / serial interfaces * Cellular/GPS capabilities * Existing Android software/application For vehicle data, we are connecting through the truck manufacturer's approved **RP1226/J1939 interface** rather than splicing directly into the vehicle CAN harness. Our current target vehicles include: * 2025 Peterbilt 567 * 2026 Mack Granite * Additional Class 7/8 vocational trucks later We are already working with J1939 data such as: * Engine RPM * Vehicle speed * PTO status * PTO hours * Engine/vehicle status * Other telemetry available through the OEM network ## What We Want to Control In addition to reading vehicle data, customers want to remotely operate body equipment such as: * Blower ON/OFF * Work lights * Solenoid valves * Auxiliary equipment * Hydraulic/body functions * PTO request/control where supported by the OEM * PTO engine RPM increase/decrease where supported The N777S digital outputs are **open-drain outputs**, so our intended architecture is for the tablet or an external I/O controller to switch low-current control signals, relays, contactors, or body-controller inputs rather than directly powering large loads. For example: ```text Remote / Phone | | Bluetooth / RF v N777S Android Tablet | | CAN / GPIO / RS485 v Automotive I/O / Relay Controller | +---- Blower +---- Lights +---- Solenoid valves +---- Auxiliary equipment +---- OEM PTO interface ``` We are also evaluating whether the operator should use: * Bluetooth through the N777S * A dedicated industrial RF handheld remote * A CAN/J1939-capable remote receiver * Or a combination of these We would like the engineer to help us determine the best production architecture. ## PTO Integration PTO integration is an important part of the project, but we do **not** want to bypass factory interlocks or safety systems. Different truck, engine, transmission, and PTO configurations use different OEM interfaces. The system should work with OEM-approved body-builder/PTO connections and preserve conditions such as: * Park brake status * Transmission state * PTO enable conditions * Engine conditions * OEM PTO interlocks * Communication health * Emergency/fail-safe behavior We have Peterbilt/PACCAR body-builder documentation and are also working with Mack body-builder documentation. We need someone who understands that **PTO engagement, PTO feedback, PTO Mode Control, and engine RPM control may be separate functions depending on the vehicle configuration**. We do not want an engineer who simply starts transmitting guessed CAN messages onto the vehicle network. ## What We Need Help With We are looking for someone who can assist with both hardware architecture and software integration. Responsibilities may include: 1. Review our existing N777S hardware, application, wiring, and system architecture. 2. Validate RP1226/J1939 connections for Peterbilt, Mack, and eventually other heavy-duty OEMs. 3. Help identify and decode the required J1939 PGNs/SPNs for vehicle and PTO status. 4. Help implement reliable CAN communication with the Android application. 5. Validate the N777S open-drain digital output implementation. 6. Design safe interfaces between tablet GPO outputs and: * Automotive relays * Contactors * Solenoids * Body controllers * OEM PTO inputs 7. Recommend an appropriate external automotive I/O controller if the N777S's three outputs are insufficient. 8. Help design remote equipment control using Bluetooth and/or an industrial RF handheld remote. 9. Develop or assist with Android software for: * GPIO control * CAN/J1939 communication * Bluetooth communication * Equipment command logic * Equipment status feedback * Fail-safe behavior 10. Help us create a repeatable wiring harness and installation design suitable for deployment across multiple trucks. 11. Assist with bench testing and vehicle testing. 12. Document the final pinouts, wiring, CAN messages, state machines, and installation procedures. ## Example Control Logic For a simple body function such as a blower: ```text Operator presses BLOWER ON | v Remote command received | v Validate vehicle/equipment conditions | v Activate digital output | v GPO sinks control line LOW | v Automotive relay/body controller activates blower | v Feedback input confirms blower operation | v Application displays BLOWER RUNNING ``` We want **commanded state and confirmed state to be separate**. The application should not show that equipment is running simply because an output was activated. ## Important Reliability Requirements This system will eventually be installed on commercial trucks, so we need production-minded engineering. The design should account for: * Automotive voltage transients * 12 V and 24 V vehicle systems * Grounding * Proper fusing * Flyback suppression on inductive loads * Relay/contactor sizing * CAN termination requirements * J1939 wiring practices * Ignition cycling * Tablet reboot/crash behavior * Lost Bluetooth/RF communication * Watchdog behavior * Outputs returning to safe states * Equipment feedback * EMI/EMC considerations * Environmental exposure * Serviceability * Connector and harness selection A software crash or lost wireless connection must not leave a momentary control such as RPM increase/decrease unintentionally asserted. ## Ideal Engineer Strong candidates will have experience with several of the following: * SAE J1939 * CAN bus * SocketCAN * Heavy-duty trucks * Peterbilt / PACCAR * Mack / Volvo Trucks * Body-builder electronics * PTO systems * Allison / Eaton / PACCAR transmissions * Vocational truck equipment * Android hardware integration * Android GPIO * Bluetooth Low Energy * Embedded Linux * Automotive relays and I/O * Deutsch DT connectors * RP1226 * Automotive wiring/harness design * CAN analyzers * CAN logging and replay * Industrial RF remote systems * Mobile hydraulic equipment Experience with equipment such as refuse trucks, vacuum trucks, blowers, dump bodies, utility trucks, concrete equipment, tankers, hydraulic systems, or similar vocational vehicles would be especially valuable. ## Existing Resources We Can Provide We already have: * N777S rugged Android tablet * N777S technical/user documentation * Existing Android application * CAN interface * GPIO interface * Peterbilt body-builder documentation * Mack body-builder documentation * RP1226 connector information * Deutsch connectors and harness components * Access to trucks for testing * Initial J1939/PTO research * Initial wiring concepts This is **not a project starting from zero**. We need an experienced engineer to review what we have, identify anything that is incorrect or unsafe, and help us turn it into a robust system. ## Initial Milestone For the first milestone, we would like the engineer to: 1. Review our existing architecture and documentation. 2. Conduct a technical call with our team. 3. Review the N777S CAN/GPIO capabilities. 4. Review our Peterbilt 567 and Mack Granite integration plan. 5. Recommend the production architecture for remote body-equipment control. 6. Define how the tablet, CAN network, external I/O, relays, and wireless remote should interact. 7. Produce a preliminary wiring/block diagram and implementation plan. If the initial engagement goes well, this could become an ongoing relationship involving development, testing, additional truck platforms, and production deployment. ## When Applying Please include: * Your experience with SAE J1939/CAN * Heavy-duty truck projects you have worked on * Any Peterbilt/PACCAR or Mack/Volvo experience * Experience with PTO/body-builder interfaces * Android or embedded software experience * Experience designing automotive relay/I/O systems * CAN tools you normally use * Whether you can assist with both hardware and software * Your availability for ongoing engineering support Please describe a similar vehicle-control or heavy-equipment project you have personally worked on. We are looking for someone with practical vehicle integration experience, not only general embedded software experience.