Connects the ECU to the engine sensors, actuators and the vehicle CAN network.
Concentrically twisted tinned copper with Tefzel insulation, Deutsch DTM connectors at sensors and breakouts, DR-25 heat shrink over the bundle.
No part-specific design process is documented. The Electrical Harness subsystem design process applies: 1. Collect the sensor list and the datalogger assignment for each sensor. 2. Draw the harness in RapidHarness: main connectors, sensor connectors, connections, then bundles and split points. 3. Order wire early. BMRSWired lead time has run 2 weeks to 3 months and is the single highest-impact long lead item. 4. Cut and crimp terminals, assemble connectors, build service loops. 5. Twist the harness, cover with DR-25 heat shrink, test fit on the frame, then install and recover transition boots and connector boots.
Designed in RapidHarness: place the main ECU connector, place the sensor connectors, connect them, then form bundles and choose split points. Splices are grouped in one area for serviceability. Wire is cut, terminals crimped, connectors assembled with service loops, then the harness is twisted, covered in DR-25 and test fitted on the frame before connector and transition boots are installed.
M22759/18 and /32 tinned copper with Tefzel insulation, 8-22 AWG. Raychem DR-25 heat shrink. Deutsch DTM/DT connectors. RT125 epoxy and Kevlar binder.
CR22 Issue Log, 2023-08-26, Electrical. The right radiator inlet sensor read 195 C on the C185. A short was suspected in the harness with no known location, and removing the whole harness was considered. Diagnosis progressed by checking for shorts at the harness sensor connector, then at the C185 connector, then depinning the R WTR TMP IN connector, where the short was found. The wire had been crushed between the right radiator top tab and its mount. Fixed by cutting the branch back to before the crushed section, putting the connector there, and lengthening the sub-harness. From the Car Wiring Lessons Learned document, the recurring harness failures are: wires melting near the exhaust without heat protection, Weather Pack connectors not all being indexed the same (a spare harness was wired with connectors that then did not fit the sensor connectors), connectors placed where they cannot be rotated on and off, and connectors on designed parts left inaccessible (the MAP/IAT combination sensor pointed at a frame tube and was impossible to connect).
Harness branch cut back before the crushed section with the connector relocated there and the sub-harness lengthened. Connector accessibility is now a design check after the MAP/IAT sensor was found impossible to connect where it was pointed.
Nothing in CrimsonStorage covers these yet.