12/06/2026 6:12 am
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Automotive Q&A
CAN resistance changes from 60 to 120 ohms when the harness is moved
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A 2014 Jeep has intermittent no-communication with the transmission and ABS modules. With power down and the network asleep, DLC pins 6 and 14 measure 60.4 ohms. Moving the harness near the transmission bracket makes the reading jump to about 120 ohms and several modules disappear on the next key cycle.
Does 120 ohms here identify an open terminator branch, and how can I narrow the side of the network without disconnecting modules at random?
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13/06/2026 10:31 am
A stable 120-ohm reading usually means only one of the two terminating resistors remains visible, but first verify the vehicle topology and that the network is fully powered down. Use the diagram to identify splice points and which terminating module is on each end. Split the bus at an accessible connector or splice, then measure each side while reproducing the harness movement.
Do not ohm-test a powered bus. Once the affected side is known, scope CAN high and low at points before and after the suspect section; an open branch will preserve waveform on one side and lose it on the other.
Topic starter
14/06/2026 8:42 am
The transmission-side branch went open when the loom touched a stamped bracket. One CAN conductor had broken inside insulation that looked intact. A sealed splice restored 60.2 ohms through the full movement range, and repeated network scans stayed complete.