Aston Martin diagnostic trouble code

P0862: TCM To PCM Heartbeat Signal Short To Supply

Use this reference to understand the recorded condition, confirm the available V8 Vantage or DB9 manual coverage, and follow the documented diagnostic checks before replacing parts.

Code family
Powertrain
Vehicle system
Transmission
Manual coverage
DB9
Warning-lamp status
DB9: Non-MIL

What Aston Martin code P0862 means

TCM To PCM Heartbeat Signal Short To Supply

DB9 preliminary diagnostic manual · section 2-196

Manufacturer fault-analysis procedure

Cautions and notes

NOTE: The Heartbeat signal is a square wave signal
switching between 0 and 5 VDC at 10Hz.

Test sequence and decision path

1. Connect the WDS and confirm that P0860,
P0861 or P0862 is logged. Clear the logged fault
code.

2. Access the transmission connector C0932. Measure the resistance from harness connector C0932-
11 to C0932-7. The resistance should be 1.4 KΩ.
If 1.4 kΩ is measured, go to step 3.
If significantly more than 1.4 k Ω is measured,
service the high resistance or open circuit from
C0932 to the Interface-Auto Switches unit.
Reconnect all components. Clear the fault code.
Retest to ensure that the problem is resolved.

3. With the ignition on, measure the voltage from
C0932-11 to ground.
If the voltage at pin C0932-11 is 0 volts, go to
step 4.
If the voltage is significantly above 0volts, service
the short circuit to supply. Retest by running a
KOEO test to ensure that the problem is resolved.

4. Measure the resistance from pin C0932-11 to
ground.
If the reistance is high, no short to ground is
present and testing is complete.
If the resistance is low, service the short circuit to
ground on this line. reconnect all components
and retest to ensure that the problem is resolved.
Open the corresponding manual page for wiring diagrams and figures