Bobcat H4602 (46-02) Fault Code: Left Blinker Error On
Also shown on the panel as 46-02
Left Blinker Error On · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
H4602 (panel code 46-02) sets when the Bobcat auxiliary controller sees voltage on the left blinker relay signal wire 6420 when the left blinker switch has not been activated. It points to a short to supply voltage on that wire, a stuck or faulty relay, a controller fault, or corroded/damaged connectors in the AWS horn/blinker or mainframe harness.
Low severity. This code affects turn signal operation, not machine performance, hydraulics, or lifting function. It should still be fixed before road or jobsite travel since a non-working or falsely-triggered blinker is a visibility and legal safety issue, especially on public roads.
What does Bobcat error code H4602 mean?
H4602 is set by the auxiliary controller when it detects voltage present on the left blinker relay's signal wire, wire 6420, at a time when the left blinker switch on the left grip has not been activated. In normal operation, pressing the left blinker switch sends a command to the auxiliary controller, which then energizes the left blinker relay. This code means the controller is seeing that same voltage show up without the command being given.
In plain terms, something downstream is feeding power back into a wire that should only carry voltage when you actually hit the blinker switch. That usually points to a wiring short, a stuck relay, or a corroded connector rather than a problem with the switch itself.
This is a signal integrity fault on the lighting circuit. It will not shut the machine down or affect drive, lift, or hydraulic systems, but it does mean your left turn signal may not be working correctly or may be staying on unexpectedly.
Common causes of H4602
- Signal wire 6420 shorted to supply voltage, feeding voltage into the circuit when the blinker switch is not pressed.
- Faulty left blinker relay that is stuck closed or otherwise passing voltage without a command.
- Fault within the auxiliary controller itself.
- Moisture, corrosion, or pushed-back pins in the auxiliary controller connectors, the AWS horn/blinker harness, or the mainframe harness.
- Intermittent causes that may not be found if the code is not active at the time of testing: loose connections, corrosion, pushed-back pins, the controller, the wire harness, or a combination of these problems.
How to troubleshoot Bobcat H4602: first checks
- Confirm the code is present with the key switch/(run/enter) on, since this is the condition under which H4602 sets.
- Visually inspect the auxiliary controller connectors, the AWS horn/blinker harness, and the mainframe harness for moisture, corrosion, or pins that have pushed back out of their connector body.
- Check wire 6420 for signs of chafing, pinching, or contact with a supply voltage wire that could cause a short.
- Test the left blinker relay for proper operation, confirming it is not stuck closed or passing voltage without being commanded.
- If the code is not currently active, treat it as intermittent and recheck all connectors and harness routing for loose connections or corrosion that may not show up under a static test.
How the code clears
Once the repair is complete, clear the code by cycling power (turning the key switch off and back on). No separate clearing step is listed.
Affected models and serial ranges
H4602 appears in our records across 16 Bobcat models. Match your machine by model and serial number.
| Model | Serial ranges |
|---|---|
| S510 | SN A3NJ11001-99999, SN A3NK11001-99999, SN ATZC11001-99999 |
| S530 | SN A7TV11001-99999, SN ATZD11001-99999 |
| S550 | SN A3NK11001-A3NL99999, SN A3NM11001-99999 |
| S570 | SN A7U711001-799999, SN A7U811001-899999 |
| S590 | SN ANMN11001-99999, SN ANMP11001-99999 |
| S630 | SN A3NT12370-99999, SN A3NU11001-11111, SN A3NU11112-99999 |
| S650 | SN A3NV11001-13098, SN A3NV13099-99999, SN A3NW11001-11248, SN A3NW11249-99999 |
| S750 | SN A3P211001-299999 |
| S770 | SN A39511001-99999, SN A3P411001-99999 |
| T550 | SN A7UJ11001-AJZV12276 |
| T590 | SN ALJU11001-999999, SN B37811001-999999, SN B3Z711001-999999 |
| T630 | SN A7PU11001-11663, SN A7PU11664-99999 |
| T650 | SN A3P012214-099999, SN A3P111242-199999 |
| T750 | SN ANKA11001-A99999 |
| T770 | SN A3P811001-899999, SN A3P911001-999999 |
| T870 | SN A3PG11001-99999, SN A3PH11001-99999 |
Frequently asked questions
What does Bobcat code H4602 mean?
It means the auxiliary controller detected voltage on the left blinker relay signal wire 6420 without the left blinker switch being activated. It is a wiring/relay/controller fault on the left turn signal circuit.
What is the panel display version of H4602?
On the display panel, this code shows as 46-02.
Will H4602 stop my Bobcat from driving or operating?
No. This code affects the left blinker circuit only. It does not disable drive, hydraulics, or lift functions, but it should be repaired for safe road use.
What usually causes this code?
The most common causes are signal wire 6420 shorting to supply voltage, a faulty left blinker relay, moisture or corrosion in connectors, or an auxiliary controller fault.
Why does the code come and go?
Intermittent H4602 codes are usually caused by loose connections, corrosion, or pushed-back pins that only cause a fault under certain vibration, moisture, or temperature conditions. If the code is not active during testing, the exact cause may not be found right away.
How do I clear H4602 after fixing it?
Cycle the key switch off and back on. No other reset procedure is listed.
Which Bobcat models can show code H4602?
This code applies to the S510, S530, S550, S570, S590, S630, S650, S750, S770, T550, T590, T630, T650, T750, T770, and T870 models.