1968-1970 Dodge & Plymouth B-Body Wiring Harnesses: Under-Dash, Engine, Front Light or Rear? How to Order the Right One

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1968-1970 Dodge & Plymouth B-Body Wiring Harnesses: Under-Dash, Engine, Front Light or Rear? How to Order the Right One

A brittle, hacked-up harness is behind a lot of the gremlins in a 50-year-old Mopar: dash lights that flicker, a gauge that reads nothing, a turn signal that quits on a bump. Replacing the harness is one of the best things you can do for a B-body you plan to drive. The catch is that Chrysler didn't build one harness. It built several sections that plug into each other, and each section changed by year, model, engine and options.

This guide covers the 1968, 1969 and 1970 Dodge and Plymouth B-bodies: Charger, Coronet, Super Bee, Belvedere, GTX, Road Runner and Satellite. Everything below comes straight from our supplier's listings. Where a listing leaves a question open, we say so.

Step 1: Know which section you're replacing

  • Under-dash harness. This connects to the switches and sensors behind the dash. It also attaches to the engine harness and runs down the side cowl panel to connect to the rear body harness. It's the biggest and most expensive section.
  • Engine harness. This runs the engine bay. Our supplier lists the stock-style engine harnesses with connections for the temperature sending unit, oil light, coil power, horn relay and washer pump motor.
  • Front light harness. This one powers the headlights, park lamps and turn signals up front. Our supplier notes these are for cars that use a separate engine harness, and that the firewall connector can be a single plug or two depending on the model.
  • Rear body light harness. This powers everything at the back of the car and connects to the under-dash harness (on some cars, through an intermediate harness).

Before you order any of them, look at your original harness. Our supplier's warning applies to every under-dash harness here: Chrysler often added separate wire assemblies depending on the car's final configuration, many of those aren't reproduced, and you may need to reuse them from your original harness.

Step 2: Under-dash harness, by year and oil gauge

The question here is whether your dash has an oil warning light or an oil pressure gauge.

Step 3: Engine harness, by engine and ignition

Two questions decide the engine harness: is it a Six-Pack car, and is it still running the stock breaker-point ignition or has it been converted to electronic ignition (the listings call this "with ECU," for the electronic control unit)?

Converting a points car to electronic ignition but keeping the original engine harness? There's a conversion harness for that: electronic ignition conversion harness (MN2197), for 1964-72 B-bodies with a B, RB or Hemi engine and a point-style engine harness. It works with any electronic distributor and control unit. You'll also need a 4-wire ballast resistor, the electronic distributor and the control unit.

Fusible links are built into the engine and forward light harnesses. If yours is the only bad part, the 1967-70 B-body engine/forward light fusible link (MB1803) is the same link the harnesses use.

Step 4: Front light harness, by model

Here the model matters, because the Charger's hidden headlights and the Plymouth's turn signal locations changed the wiring.

We don't have a verified front light harness listed for the 1970 Dodge Coronet and Super Bee yet. Ask us and we'll check with our supplier.

Step 5: Rear body light harness, by model and body style

Got a tach? Don't forget its harness

The tachometer has its own dash-side harness, and it depends on whether the car has the factory Rallye gauges. For 1968-70 B-bodies there's one with Rallye gauges (MB1822) and one without Rallye gauges (MB1823).

Quick checklist before you order

  1. Year and model (Charger, Coronet/Super Bee, or Plymouth Belvedere/GTX/Road Runner/Satellite).
  2. Engine, and whether it's a Six-Pack.
  3. Ignition: stock breaker points or electronic.
  4. Oil light or oil gauge, and Rallye gauges or not.
  5. Body style for the rear harness (coupe, convertible or wagon).
  6. Pull a panel and look at your original harness for any add-on wire assemblies you'll need to reuse.

Working on a Barracuda, Challenger, Dart or Duster instead? Browse all our Mopar wiring harnesses. Not sure which section you need? Send us your year, model, engine and options and we'll match the harness before you order.