Professional•Automotive•Diagnostic Solutions•All Makes & Models•Domestic • Import • Euro•OEM Approved
DLC PINOUT
16-Pin Diagnostic Link Connector — Pin Map & Quick Electrical ChecksEvery OBD-II vehicle uses the same 16-pin SAE J1962 connector, but which pins carry which protocol still trips people up mid-diagnosis. This reference maps every pin and gives you fast go/no-go electrical checks you can run at the DLC before you even plug in a scan tool.
DLC Pin Map — Looking Into the Vehicle's DLC Socket (Mating Face)
1
OEM
2
J1850+
3
OEM
4
Chassis Gnd
5
Signal Gnd
6
CAN-H
7
K-Line
8
OEM
9
OEM
10
J1850−
11
OEM
12
OEM
13
OEM
14
CAN-L
15
L-Line
16
Battery+
Pins 6, 14 · CAN High / Low
Pin 16 · Battery Power
Pins 4, 5 · Grounds
Legacy Protocols · J1850 / K-Line / L-Line
Manufacturer Discretionary
Pins 1–8
1
Manufacturer Discretionary
Not defined by SAE standard — each OEM assigns this pin as needed. On GM vehicles (about 2006 and later) this is the single-wire CAN (GMLAN low-speed) body bus.
GM Single-Wire CANOther OEMs vary
2
SAE J1850 Bus+
PWM or VPW communication line, used on pre-CAN domestic vehicles. If present, expect pin 10 to carry the complementary Bus− line (PWM only).
GM Class 2 (VPW)Older Ford (PWM)
3
Manufacturer Discretionary
Not defined by SAE standard. On Ford this is commonly the medium-speed CAN (MS-CAN) high line, paired with pin 11. Older Chrysler platforms used it for the CCD bus.
Ford MS-CAN+Older Chrysler CCD+
4
Chassis Ground
Hard ground reference to the vehicle chassis. Should read near 0Ω back to battery negative (after subtracting meter-lead resistance) on every vehicle.
Always Present
5
Signal Ground
Dedicated reference ground for the diagnostic signal lines, kept separate from chassis ground to reduce noise on the data circuits.
Always Present
6
CAN High (CAN-H)
High-speed CAN bus, ISO 15765-4 / SAE J2284. Mandatory on all US vehicles 2008+. Pairs with pin 14 — this is where your 60Ω resistance check lives.
ISO 15765-42008+ Mandatory
7
ISO 9141-2 / ISO 14230 K-Line
Single-wire K-Line used by ISO/KWP2000 vehicles, mainly pre-2008 European and Asian imports. Often paired with pin 15 (L-Line) as a backup line.
Pre-2008 Euro/Asian
8
Manufacturer Discretionary
Not defined by SAE standard — reserved for OEM-specific use, varies by manufacturer and platform.
Varies by OEM
Pins 9–16
9
Manufacturer Discretionary
Not defined by SAE standard — reserved for OEM-specific use, varies by manufacturer and platform.
Varies by OEM
10
SAE J1850 Bus−
Complementary line to pin 2 on PWM-based J1850 systems only — VPW systems use pin 2 alone and leave this pin unused.
PWM Only
11
Manufacturer Discretionary
Not defined by SAE standard. On Ford this is commonly the medium-speed CAN (MS-CAN) low line, paired with pin 3. Older Chrysler platforms used it for the CCD bus return.
Ford MS-CAN−Older Chrysler CCD−
12
Manufacturer Discretionary
Not defined by SAE standard — reserved for OEM-specific use, varies by manufacturer and platform.
Varies by OEM
13
Manufacturer Discretionary
Not defined by SAE standard — reserved for OEM-specific use, varies by manufacturer and platform.
Varies by OEM
14
CAN Low (CAN-L)
High-speed CAN bus return, ISO 15765-4 / SAE J2284. Pairs with pin 6 — this is the other half of your 60Ω resistance check.
ISO 15765-42008+ Mandatory
15
ISO 9141-2 / ISO 14230 L-Line
Init/wake-up line paired with pin 7 K-Line on ISO/KWP2000 systems, used mainly for the initial wake-up sequence on some platforms.
Pre-2008 Euro/Asian
16
Battery Power (B+)
Always-hot, fused power feed straight from the battery — powers the scan tool itself. No voltage here means nothing downstream will talk, scan tool included.
Always HotFused
Quick Checks — No Scan Tool Required
CAN Bus Resistance
Pins 6 & 14
Key off, modules asleep (~2 min after last door close), battery disconnected or ignition fully off. DMM on ohms, probe pin 6 (CAN-H) to pin 14 (CAN-L) at the DLC.
~60Ω = Healthy
~120Ω = One Terminator Missing / Open Branch
OL = Open Circuit
~0Ω = Shorted
CAN to Ground / B+
Pins 6 & 14
Check pin 6 and pin 14 individually to ground (pin 4) and to B+ (pin 16). Either should read open — continuity here points to a chafed harness shorting the bus, not just a bad resistor.
OL to Gnd & B+ = Healthy
Continuity = Chafed Harness
Battery Power
Pin 16
Probe pin 16 to pin 4 (chassis ground). Should read battery voltage key-off. No voltage means a blown DLC fuse or open feed — nothing downstream communicates until it's fixed.
~12.4–12.8V = Healthy (Resting)
Below ~12.2V = Weak Battery — Charge & Test
0V = Fuse/Feed Open
Ground Integrity
Pins 4 & 5
Continuity from pin 4 and pin 5 to a known-good chassis/battery negative point should read close to 0Ω after subtracting your meter-lead resistance (short the leads first — they often read 0.1–0.3Ω). For a better test, voltage-drop the grounds with the circuit loaded. Ground resistance causes intermittent faults that mimic a "no comm" module.
Under ~0.5Ω (Leads Subtracted) = Healthy
Higher = Ground Fault
Important Notes
Never check DLC resistance with the circuit powered — false readings and possible meter damage. Confirm key-off and modules asleep, or disconnect the battery first
~60Ω across pins 6/14 confirms the bus itself is intact — a "no comm" complaint at that point usually points to a specific module, not the bus, so start backprobing from there
Pins 1, 3, 8, 9, 11, 12, and 13 have no universal standard — always confirm manufacturer-specific use with OEM wiring diagrams before probing or backprobing them
A healthy 60Ω reading does not rule out intermittent faults — a bus that tests fine at rest can still drop out under vibration or heat from a marginal connector or chafe point
Pre-2008 vehicles may use J1850 (pins 2/10) or ISO/KWP2000 (pins 7/15) instead of CAN — confirm protocol before assuming pins 6/14 will show a reading at all
Some aftermarket harnesses and OBD-II splitters add their own termination — if resistance reads oddly low with everything else healthy, check for an aftermarket device on the bus
Free reference sheet — get all 270 diagnostic sheets at kissdiagnostics.com